Uncaging stent

ABSTRACT

A stent (scaffold) or other luminal prosthesis comprising circumferential structural elements which provides high strength after deployment and allows for scaffold to uncage, and/or allow for scaffold or luminal expansion thereafter. The circumferential scaffold may be formed from degradable material, or may be formed from non-degradable material and will be modified to expand and/or uncage after deployment.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of PCT Application No.PCT/US2017/032748, filed May 15, 2017, which claims the benefit ofprovisional patent application nos. 62/480,121 , filed Mar. 31, 2017;62/430,843, filed Dec. 06, 2016; 62/424,994, filed Nov. 21, 2016;62/414,593, filed on Oct. 28, 2016; 62/374,689, filed on Aug. 12, 2016;and 62/337,255, filed on May 16, 2016 the full disclosures of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Balloon angioplasty was introduced to open vessels, particularly bloodvessels which have narrowed as a result of plaque progression or a heartattack. In successful cases, the blood vessel remained open and/orexhibited positive remodeling over time and/or exhibited vasodilationability mimicking to a degree the natural vessel ability. In othercases, however, the blood vessel would re-occlude within few days orwithin months due to various causes such as recoil of the vessel,thrombus formation, or other type of plaque morphology progression.

Metallic stents were developed to provide a structure, often referred toas a scaffold, with sufficient radial strength (crush resistance) toaddress recoil and hold the vessel open over time. Stents were formedfrom wire(s), coils, braids, a sheet, and/or tubular bodies. Balloonexpandable stents formed from patterned non-degradable metallic tubes,wires, or sheet, are now most commonly used as they display desirablestructural characteristics such as limited inward recoil, high strength(crush resistance or crush force), and limited axial shortening uponexpansion, when compared to some earlier coiled or braided stents.

Despite their success and widespread adoption, metallic stents such asstainless steel alloys, Platinum iridium alloys, and cobalt chrome alloystents, suffer from certain shortcomings, such as they jail the lumen orvessel, they do not further expand (after inward recoil) afterimplantation under physiologic conditions, preventing the lumen orvessel from further expanding which in turn inhibits positiveremodeling, and/or such stent inhibits vasodilation or vasomotion of thetreated vessel stent segment which is important to healing of the vesselor the normal functioning of the vessel. This phenomenon is commonlyreferred to as “jailing” or “caging” the vessel. High radial strength isimportant to support a body lumen upon implantation and/or tomaintaining it open upon implantation of the stent and/or high strengthis important in preventing the lumen from getting smaller afterimplantation. In some cases where shape memory self expandable alloysstents are used such stents typically do not exhibit high radialstrength (high crush force resistance) like the metallic stents due tothe material properties (and as a result the lumen in some cases becomesmaller after implantation of such stents due to excessive inward recoildue to lumen inward force on the stent and/or due to the lower radialstrength of these stents, making such stent less likely to furtherexpand after implantation in a lumen or diseased lumen segment, and/orsuch stents are less likely to exhibit vaso-dilatation or vaso-motion ofthe stented segment. In some cases shape memory stents penetrate thelumen wall moving towards the adventitia causing irritation,inflammation of the vessel or lumen, sometimes resulting in unwantednegative clinical events and/or re-occlusion of the body lumen orvessel. Also, the stent is typically maintained in the crimpedconfiguration using a constraint upon delivery into the vessel or lumenwhich makes the profile of the stent system large and less deliverable.Stents of this type are usually pre-programmed to expand to a certaindiameter/configuration which makes sizing limited to such pre-programmeddiameter/configuration and less likely to expand or maintain an expandeddiameter beyond such pre-programmed diameter, which makes stent sizingmore difficult, and/or such stents do not expand further beyond suchpre-program diameter/configuration after deployment, to name a few.

To address some of these shortcomings, biodegradable stents or scaffoldsmade from metallic or polymeric materials were developed. By allowingthe stent to degrade or resorb, the jailing or caging effect woulddiminish or decrease over time and the scaffold would finally disappearover time. Present biodegradable stents, however, and in particularpolymeric biodegradable stents and corrodible metallic stents, havetheir own shortcomings, including stent fractures, and/or limitedability to over-expand the stent above a nominal expanded diameter,and/or have excessive or high initial inward recoil, and/or haveadditional inward recoil after implantation and after the initial inwardrecoil. In some cases they may have insufficient strength to accommodatevarious lesion types after deployment, and/or limited ability tomaintain a lumen or vessel open after deployment. Biodegradable stentstypically have lower radial strength (crush resistance/strength) thanballoon expandable metallic non-degradable stents, typically are bulkythick strut stents in order to address some of the mechanicalshortcomings such as suboptimal crush strength, or having thick struts,which can cause negative clinical events, may cause excessiveinflammation (due at least in part to the degradation of the materialand the quantity of the degradation material), and/or cause excessivehyperplasia such as neo-intimal hyperplasia (due to at least in part tothe degradation of the material and the quantity of the degradationmaterial), to name a few problems.

Attempts have also been made to make scaffolds from a combination ofpolymeric and metallic materials. However, such designs have displayedtheir own shortcomings. Such combination designs can lack sufficientinitial crush resistance to effectively open a lumen, or maintain itopen, after implantation of the stent, or such designs do not uncage thestent, or do not uncage the stent along the entire stent segment, or donot uncage the vessel, or do not further expand the stent underphysiologic conditions, or do not further expand the stent and/or allowit to contract using or after use of vaso-dilators and/orvaso-constrictors after implantation. Alternatively, some other suchdesigns will not be able to further expand to a larger configuration(after inward recoil if any) after implantation. Still other designshave so many separate metallic or other non-degradable pieces that theyrisk releasing the small pieces into the blood stream potentiallycausing a clinical event. One or more needs as described above in thefollowing exemplary issues remain unmet by present non-degradablestents: having a stent with low inward recoil, and/or having a stentwith low initial inward recoil after expansion while the diameter of thestent is substantially maintained after implantation and after theinitial inward recoil, and/or having a non-degradable stent configuredto be able to further expand (after inward recoil if any) afterdeployment under physiologic condition, and/or having a stent able toexpand or further expand (after inward recoil if any) after deploymentwithout a pre-programmed temperature trigger setting or without apre-programmed expanded diameter/configuration setting, and/or having astent able to expand or further expand (after inward recoil if any)without a programmed temperature, and/or having a stent able to furtherexpand (after inward recoil if any) after deployment under physiologiccondition without penetrating or without substantially penetrating thevessel or lumen wall into the advantitia, and/or having a stent thatdoes not cause excessive inflammation, and/or having a stent that doesnot penetrate the lumen or vessel wall after implantation into theadvantitia, and/or having a stents that expands further following anyinward recoil, after deployment (implantation) further expanding thelumen or vessel diameter, and/or having a stent maintained orsubstantially maintained in the crimped configuration upon delivery intothe vessel or lumen without a constraint and which further expands afterany inward recoil to a larger configuration after deployment, and/orhaving a stent that can be deployed to a wide range of diameters andstill uncages the vessel or lumen after deployment, and/or having astent that can be deployed to a wide range of diameters and stillfurther expand after any inward recoil to a larger configuration afterimplantation, and/or having a stent able to further expand after anyinward recoil beyond the pre-programmed expanded diameter/configurationafter implantation, and/or having a stent that exhibit vaso-motion,vaso-dilation, or vaso-constriction, after implantation, and/or having astent that has sufficient strength after deployment to support a bodylumen, has low inward recoil, and where the stent exhibits radial strainof 1% or larger than 1% after deployment, and/or having a non-degradablestent having an initial compliance upon expansion from a crimpedconfiguration to an expanded configuration, wherein the initialcompliance increases after implantation, and/or having a non-degradablestent having an initial radial strength (crush resistance) uponexpansion from a crimped configuration to an expanded configuration,wherein the initial radial strength decreases after implantation, and/orhaving a balloon expandable non-degradable stent capable of expandingfrom a crimped configuration to an expanded configuration, where theexpanded configuration comprises diameters ranging from 2.0 mm to 4.0mm, and wherein the stent exhibits initial inward recoil after aninitial expansion, and said stent after initial recoil has an initialdiameter, said stent maintains said initial diameter (or configuration)after said initial inward recoil, and wherein the stent responds to avaso-dilator after implantation sufficient to expand the stented segmentto a second diameter wherein the second diameter (or configuration) islarger than the initial diameter.

A particular concern in vascular and other body lumens afterimplementation of the stent or other prosthesis is the loss of vessel orlumen remodeling or enlargement, or the loss of vessel or compliance orcontractility, referred to above as “caging” or “jailing” of the bloodvessel or body lumen. Vessel compliance is necessary for the vessel orbody lumen under physiologic conditions such as responding to changes inthe internal pressure, external pressure, muscle contraction, musclerelaxation, chemical change, and the like. Such changes can result frommany sources, such as the presence of natural, or artificial substances,which can relax or contract the body lumen and/or muscles such as smoothmuscle cells, for example within the walls of the body lumen. Theimplantation of a stent in a blood vessel or body lumen will necessarilycontribute to a reduction in the overall or “composite” compliance ofthe body lumen and the stent. Each of the body lumen's naturalcompliance and the stent's additional compliance will contribute to atotal or overall “composite” compliance which will necessarily be lessthan that of the body lumen had the stent not been implanted. Thus, itis desirable for a stent implanted in body lumen, particularly implantedin a blood vessel, to minimize the reduction of body lumen compliancewhich naturally occurs as a result of the implantation of the stent.While a reduction of the compliance may be acceptable for a period oftime immediately following implantation, particularly during that period(such as upon implantation or the initial period after implantation)when high radial strength is desired to maintain patency of the vessel(or body lumen) and prevent further inward recoil after implantation.Such strength is less necessary or not necessary after the initialperiod when healing of the vessel has occurred and eventually thestrength of the stent becomes unnecessary or less important. During suchhealing phase or after such healing phase, it is highly desirable thatthe compliance of the vessel returned to levels at, or approaching, orcloser to the natural compliance of the lumen in the absence of theimplanted stent. Thus, it is an object of the present invention toprovide stents, stent scaffolds, and other luminal prostheses which,after implantation, display a compliance which increases over time, inresponse to the vascular or other luminal environment, so that the totalor composite compliance of the stents scaffold and the body lumenincrease to levels which are closer or approach that of the body lumenin the absence of the stent scaffold.

Loss of compliance is also a problem for valves, rings, and otherappliances implanted in heart valve annuluses. While valve scaffolds maynot always need a high radial strength, particularly after an initialperiod of implantation, it is beneficial that they be sufficientlycompliant to be able to conform to the annulus as the annulus deformsduring the normal systoloic-asystolic cycle, or it deforms to conform tothe deformed annulus due to disease progression thus maintaining theintegrity of the valve function, or it dilates to conform to the annulusdilation due to physiologic conditions or progression of disease, whilemaintaining the integrity of valve function.

What is needed are implants, stents, stent scaffolds, vascularprostheses, ecto-prosthesis, and/or other luminal prostheses thataddresses at least some of these shortcomings as well as othersdescribed herein.

2. Listing of Background Art

Relevant background patents and applications include: U.S. Pat. Nos.7,011,678; 5,922,020; US2003/0153971; U.S. Pat. No. 9,056,157;US2005/0222671; U.S. Pat. Nos. 9,265,866; 7,169,173; 8,435,281;US2003/0195609; U.S. Pat. Nos. 7,402,168; 7,829,273; 5,695,516;6,540,777; 8,652,192; 8,128,679; 8,070,794; 6,599,314; 8,961,585;7,455,687; 7,645,409; 8,202,313; EP2229919; U.S. Pat. Nos. 6,251,134;6,409,754; 5,766,237; 5,957,975; 5,306,286; 5,961,545; 8,052,743;9,180,005; 9,192,471; US2008/177373; and US2005/283229.

SUMMARY OF THE INVENTION

The present invention provides numerous examples and embodiments ofstents, in particular vascular and luminal stents and prostheses whichdisplay strength, modified (or controlled) strength, and/or modified (orcontrolled) compliance characteristics after expansion and/orimplantation. In one particular example, metal, metal alloy, and othernon-degradable stents may be modified in numerous ways to control theirradial strengths and compliances initially at the time of expansion inthe body lumen as well as subsequently during the days, months, andyears following the initial expansion and/or implantation. Inparticular, many of the stent and scaffold designs described and claimedin the present application will provide for a variable (or controlled)compliance which has at an initial compliance, which is relatively low,and increases over time after implantation, and a radial strength whichhas an initial strength, which is relatively high (e.g. havingsubstantial hoop strength or crush resistance) at the time ofimplantation or initial expansion, and decreases (or may be reduced)over time after implantation. The increase in compliance and decrease inradial strength may occur over a time period of days, weeks, or monthsafter implantation and may be caused by any one or more of a number ofstructural transformations in a scaffold which forms all or a portion ofthe prostheses.

Methods for measuring and quantitatively expressing the strength (radialstrength) and the compliance and of vascular and other luminal stentsand scaffolds are well known and described in the patent and medicalliterature.

Compliance, as the term is used in many of the examples or embodiments,is a non-dimensional measurement which expresses a percentage change indiameter (or configuration) of a luminal structure, or a segment of aluminal structure, in response to physiologic conditions such as achange in internal pressure within or adjacent to the luminal structure,usually such change in pressure is 100 mmHg In some other instances,compliance measurement can be expressed as mm/atmosphere, mm/psi, %/atm,%/psi, or the like. The term compliance and radial compliance are usedinterchangeably.

Body lumens, stents, scaffolds, prostheses, and other tubular structureswill each have their own compliance. Body lumens having implantedstents, scaffolds, prosthesis, and other tubular structures will alsohave a compliance which is a composite of the individual compliances ofthe lumen and the implant, where the composite is typically lower thanthe lumen and many cases lower than the implant alone. In many cases orexamples, it is the “composite” compliance that will be measured todefine the compliance characteristics of the stent, however, it can alsobe in some cases the stent alone measured compliance, scaffolds,prosthesis, and other tubular structures in many of the examples beingclaimed herein. In many instances or examples throughout thisapplication, the term “radial strain” is used to mean compliance and isused interchangeably with the term “compliance” (or the compositecompliance) as the term compliance or composite compliance is describedin this or other paragraphs. Usually, when radial strain is measured at100 mmHg change in pressure, it refers to the compliance of the implant(or composite compliance), but compliance can also refer to % change indiameter of the implant or composite at a given change in pressuredifferent than 100 mmHg.

In particular, the radial compliance of a stent, scaffold, or otherluminal prosthesis will be measured as a composite compliance in vitroin a mock vessel in accordance with well-known principles andtechniques, such as those described in ASTM F2477-07R13 which measurescompliance at a pressure change of 100 mmHg, but the test can alsoprovide the method required for testing compliance at a given change inpressure other than 100 mmHg, such as at about 176 mm Hg, or otherpressure. Also, stent compliance can be tested by having a stentimplanted in a vessel, such as a coronary artery vessel, of a porcineanimal and the compliance is measured in the stented segment of thevessel.

In a first aspect or example of the present invention, a prosthesis, inparticular an endoluminal prosthesis comprises a scaffold having aplurality of circumferential rings formed or patterned from anon-degradable material, typically a metal or metal alloy, where thescaffold is configured to expand from a crimped configuration to anexpanded configuration. At least some of the circumferential rings willhave at least one separation region, where the separation region(s) areconfigured to form at least one discontinuity in the circumferentialring after the scaffold has been expanded in a physiologic environment.In a preferred example, after such expansion and exposure to thephysiologic environment, typically a vascular or other body lumenenvironment, at least two of the circumferential rings remain axiallyjoined after all discontinuities are formed, typically being axiallyadjacent rings. Frequently, all circumferential rings of suchendoluminal prostheses will remain axially joined after thediscontinuities are formed. For example, the circumferential rings maybe joined by axial links, which are typically short structural elementsjoining a region on one circumferential ring to a region on an adjacentanother circumferential ring. In other examples, however, regions onsuccessive adjacent circumferential rings may be directly joined, forexample being welded or otherwise joined crown-to-crown, strut-to-strut,or the like, as will be described in more detail hereinafter in thisapplication. In specific examples, adjacent crowns on adjacent rings maybe joined by welding, wrapping, binding with wires or other filaments,adhesives, or the like.

Such endoluminal prostheses according to the present invention, forexample, will have circumferential rings with a circumferentialstructure having an initial radial compliance, typically a compositecompliance as discussed above, prior to formation of anydiscontinuities. After formation of the discontinuities, however, atleast some of the circumferential rings will have a radial compliancewhich is increased relative to the initial radial compliance of the atleast some rings prior to formation of the discontinuities. For example,the initial radial compliance of at least some of the circumferentialrings of a scaffold (or the composite compliance of the scaffoldsegment) in accordance with the principles of the present invention maybe 0.1% to 1%, typically from 0.1% to 0.5%, while the radial complianceafter formation of the discontinuities will typically be from 1.2% to10%, often being from 1.2% to 5%, or 1.5%-3%.

The composite compliance of a scaffold may be measured using a mockvessel system as follows. The scaffold being tested, the mock vessel,the water used to pressurize the mock vessel, and all other testequipment are held at room temperature. All diameter measurements aremade with a calibrated non-contact system capable of measuring adiameter to within ±0.01 mm without contacting the scaffold. Suitablemeasurement instruments include microscopic video measuring system,laser microscopes, and optical comparator. Pressure measurements ofwater used to pressurize the mock vessel are made with a gauge that canaccurately measure fluid gauge pressure to within ±0.05 PSI. Pressuremeasurements are made at the time the diameter measurements are taken.The length of all connecting tubes used in the setup are under 10 inchesand to eliminate any restrictions in the tubes and connectors areeliminated to assure that any dynamic changes in pressure throughout themock vessel are accurately reflected by the pressure gauge. Diametermeasurements should be performed with 30 minutes from initialpressurization of the mock vessel.

The mock vessel is an elastomeric silicone tube with a uniform crosssections and uniform material properties throughout its length. Forstents smaller than 2.5 mm diameter, the mock vessel wall thickness is0.25±0.03 mm. For stents of 2.5 mm diameter and larger, the mock vesselwall thickness is 0.5 mm+0.03 mm. The test pressure within the mockvessel will be 3.4±1 PSI (or approximately 176 mmHg), and the systemwill be sufficiently leak proof to maintain this pressure for theduration of the test. The stent-mock vessel system is fixtured toprevent changes in length and of the mock vessel resulting fromlongitudinal forces) that could affect the resting length of the mockvessel and the diameter of the mock vessel. The stent-mock vessel systemis further fixtured to prevent changes in diameter from forces otherthan internal pressurization.

Balloon expandable, non-degradable scaffolds are deployed in air to anID after inward recoil from the expanded configuration which equal to or0.1 mm less than the outer diameter of the mock vessel withoutpressurization. The scaffold is expanded using a balloon or otherdelivery system suitable for use with the scaffold being tested. Theinner diameter (ID) is verified using the non-contact measuring system.Self-expanding scaffolds are deployed in air to their free diameter, andthe ID verified using the non-contact measuring system. A mock artery isselected to have an outer diameter equal to or 0.1 mm larger than theinner diameter of the deployed stent.

The expanded test scaffold is slid over the outside of the mock vessel,stretching the mock vessel tubing as necessary to temporarily reduce thetube diameter to allow the stent to be passed over it. After releasingtension on the mock vessel, actual contact between the ID of thescaffold and the outer diameter (OD) of the mock vessel along the entirecontact length is verified.

The interior of the mock vessel tube is connected to an Indeflator (aninflation/deflation device used to inflate and deflate angioplastyballoon during angioplasty) capable of providing at least 3.4 psi andhaving a gauge capable of measuring the pressure in the tube to within0.05 psi at such pressures.

The OD of the stent and the OD of a reference section of mock vesselaway from the stented segment are both measured using the non-contactsystem at a distance from the stent equal to twice the diameter of themock vessel, and a similar distance from any fixtures holding the mockvessel. Three OD measurements are made and averaged to obtain a baselinemock vessel OD value. Three OD measurements are made about themid-length of the scaffold and averaged to obtain a baseline scaffold ODvalue. The interior of the mock vessel is pressurized with water to 3.4PSI (176 mmHg), and the OD's of the scaffold and mock vessel measured atthe same locations used to establish baseline using the non-contactsystem while the pressure reading is maintained at 3.4 PSI. Thecomposite compliance is determined dividing the OD value measured whenthe mock vessel is pressurized by the baseline OD value, subtractingone, and multiplying by 100 to determine the composite compliance as apercentage.

For example, if the applied pressure in the mock vessel causes the OD ofthe test scaffold to increase in diameter from 3.50 mm OD to 3.73 mm OD,the composite compliance is ((3.73/3.50)−1)×100=6.6%. As a secondexample, if the applied pressure in the mock vessel causes the OD of thetest scaffold to increase in diameter from 3.50 mm OD to 3.52 OD, thecomposite compliance is ((3.52/3.50−1)−1)×100=0.6%.

The composite compliance of the scaffold can be measured before andafter opening of the separation regions to form discontinuities. Toobtain the composite compliance before formation of discontinuities, thescaffold is measure as described above while all separation regionsremain intact. To obtain the composite compliance after formation ofdiscontinuities, the scaffold is treated to open all discontinuitieswhile the scaffold remains on the mock vessel. The separation regionsmay be opened by techniques specific to the nature of the particularseparation region. For separation regions immobilized by polymericsleeves, glues, or solvents, the scaffold is exposed to solvents,enzymes, or other chemicals to form discontinuities, without damagingthe mock vessel. Alternatively, and for non-polymeric separationregions, the separations regions may be physically separated usingmechanical means, laser cutter, ultrasound, or other energy-basedcutters form discontinuities. For locking designs or separation regionsthat open in response to fatigue, the mock artery can be cyclicallypressurized at a 5-8 Hz rate until discontinuities form. See Example 5and FIG. 35. If the scaffold falls apart while the separation regionsare being opened, the composite compliance will be considered to beequal to mock vessel compliance without the scaffold.

Radial strength (crush resistance) is measured with parallel flat plates(reference ISO25539-2) which are fixated onto an Instron tensile testmachine with a 5N load cell to allow force and displacement measurement.The bottom plate is flat and remains stationary during testing. Theupper plate is mounted onto the load cell to record force measurement asa function of displacement. The plates are visually verified to beparallel to each other at the mating surfaces. Both the bottom and upperplates are rectangular in shape with the surfaces completely coveringthe test stent in length and diameter. Both plates are configured tostay submerged in a bath of body temperature water, maintained by acirculation heater at body temperature of 37±2° C. The circulation pumpis turned off during the force measurement to prevent currents fromaltering the results. The top plate is formed from delrin and the bottomplate is formed from brass.

A test scaffold is deployed at its nominal inner diameter using astandard indeflator or other delivery system. The deployed test stent isremoved from the delivery system and the diameter of the test stent isverified by a non-contact measuring system. The test stent is then slidonto a 0.035″ diameter mandrel approximately 50 mm in length beforeplacing between the parallel plates submerged in water at 37° C.mimicking physiological conditions. The mandrel will prevent the teststent from rolling at the initial contact with the parallel plates. Theupper plate is then slowly jogged down using the displacement controllerfrom the Instron tensile test machine until it is approximately 1 mmabove the stent, and the force gauge is zeroed. It is then lowered untilit barely touches the test stent, and a force of 0.01 N is detected. Thestent is then allowed to stabilize in the bath for 60 seconds. The testcycle is started and the crush resistance force is then measured bydecreasing distance between the parallel plates up to 50% of the teststent diameter. A force-distance curve is generated during the test. Therate of decreasing distance (crosshead speed) is 1.5 mm/min. The loadforce at 10% of stent deformation (compression) is determined inNewtons. For example, for a 3.0 mm labeled stent expanded to nominaldiameter (3.0 mm), report the force required to compress it by 0.3 mm(10% compression). The load force in Newtons (N) is then divided by theexpanded stent length in mm to normalize the strength in N to the stentlength and thus the radial strength of the stent is expressed as N/mm ofstent length.

The expanded stent baseline radial strength is measured (in N/mm ofstent length), and again after formation of discontinuities (if any), asdescribed in the crush resistance method. For a stent of the presentinvention, the radial strength decreases after formation ofdiscontinuities compared to baseline radial strength before formation ofdiscontinuities, preferably decreases compared to the baseline radialstrength, by a range from 10% to 100% of the baseline radial strength.

The above protocols for measuring composite compliance and radialstrength are particularly effective for measuring those values inscaffolds having a nominal diameter from 2 mm to 4 mm and havingdecicated or conventional deployment systems. For stents, valves,prostheses, and any other scaffold having other size and deploymentsystems, including non-standard sizes and non-standard deploymentsystems, the scaffold should be deployed according to the manufacturer'spublished instructions for use, and the test apparatus adjusted ormodified to have the same fit with the deployed scaffold, as describedabove. In the case of a mock vessel for the measurement of compositecompliance, the outer diameter of the mock vessel should be equal to orup to 0.1 mm larger than the inner diameter of the deployed scaffold. Inthe case of flat plate separation distance for measurement of crushresistance, the scaffold OD should be measured with an accuracy of ±0.01mm via non-contact methods, and 10% deflection calculated from thismeasurement. All other parts of the test methods should be followed asmuch as possible.

In preferred examples, the scaffolds of such endoluminal prostheses mayseparate into segments after the discontinuities have formed in thecircumferential rings. The separation may be along axial,circumferential, helical, irregular, or other lines. For example, two,three or more segments may separate along axial, helical, or irregularlines, allowing the segments to radially expand and contract whichincreases the composite compliance of the scaffolds when implanted in abody lumen. Often, all or substantially all of the segments will remainaxially joined along their entire lengths (or along the entire stentlength) so that, while the discontinuities provide for an enhanced (orincreased) radial compliance, the structural elements of the scaffoldsremain axially joined to continue provide support (or scaffolding) tothe lumen (or vessel) wall, and/or so that the elements are at a reducedrisk of being dislodged or otherwise released after implantation in thevasculature or body lumen. Other examples of segments include closedcell segments, and the like. In such a preferred example, the scaffold(endoluminal prosthesis) forms a tubular body in the crimpedconfiguration and/or the expanded configuration, and wherein thescaffold maybe formed from a wire, a substantially continuous tube, asheet, molding, or by printing.

In other embodiments or/and examples, the scaffold will not separateinto segments. That is, while at least one and usually a plurality ofdiscontinuities will form in the scaffold, all circumferential rings,struts, crowns, links, and other structural elements (or components) ofthe scaffold will remain physically connected so that no portion (orelement) of the scaffold is fully disconnected from the remainder of anyother portion of the stent. Such physical linkage of all portions of ascaffold even after discontinuities are formed can be an advantage asthe risk of any portion of the scaffold being released into thevasculature or other body lumen is reduced.

In one particular example, discontinuities in adjacent circumferentialrings may separate along axial lines so that the stent divides into twoor more axially aligned segments, each of which extend from a first(usually terminal) end of the scaffold to a second (usually terminal)end of the scaffold. Such axially aligned segments of the individualcircumferential rings separate circumferentially along axial (usuallystraight), helical, or irregular separation lines but remain axiallyjoined or intact (by on or more axial links for example) after alldiscontinuities are formed. Such intact axial, helical or irregularsegments will be elongated, typically having a length corresponding tothe full length of the scaffold in its expanded configuration.

While such elongated axial, helical or irregular segments will usuallybe fully separated along their entire lengths, in other cases one or twocircumferential connections may remain after all discontinuities have beformed in the scaffold. In particular, the elongated segments may remainjoined at either or both terminal end of the scaffold in order to reduce“dog-boning” or for other purposes.

In some examples, the circumferential rings of the scaffolds of thepresent invention may have continuous perimeters or peripheries, usuallycircular perimeters, in which case the adjacent continuous rings aretypically joined by axial links or by direct connection, e.g. bywelding, fusing, tying, gluing, or otherwise adhering crowns on adjacentcircumferential rings together for example In other instances, at leastsome of the circumferential rings may have discontinuous perimeterswhere the end regions are joined to form a helical scaffold. In specificexamples and embodiments, the axial links will be composed of anon-degradable metal, metal alloy, or other non-gradable material. Mostcommonly, such axial links will be patterned from the same tubularcomponent (or material) used to form the scaffolds. Thus, many scaffoldswill be formed as integral or monolithic structures from the same metal,metal alloy, or other material forming the stent.

Exemplary endoluminal prostheses of the present invention will oftencomprise scaffolds having repeating structural elements, such ascircumferential rings, closed cells, or the like. Some or all of thecircumferential rings, for example, may comprise similar or identicalstructures, e.g. a plurality of struts joined by crowns in similar oridentical patterns (but can also have varying one or more of structure,pattern, and structural elements (thickness, width, shape), etc). Theseparation regions may be located in the struts, the crowns, or both.Often, at least one separation region will be located in a strut, and atleast one to five struts within a ring will have separation regions.Alternatively or additionally, at least one separation region may belocated in a crown and from one to five crowns within a ring may haveseparation regions. Often, however, most or all crowns will be free fromseparation regions as crowns or crown regions are subjected to highstresses as a scaffold is radially expanded by balloon inflation orotherwise from a crimped configuration to an expanded configuration.Such high stresses can result in premature formation of discontinuitiesin the scaffold, and loss of structural integrity of the scaffold. Thestruts are thus a preferred location for the formation of separationregions. Separation regions may also be formed in axial links or otherregions of direct axial connection between adjacent circumferentialrings. Separation regions in axial connectors between adjacent ringstypically will not contribute to the radial compliance of the rings orthe stented segment, or typically will not affect the radial strength ofthe rings or the scaffold, after the formation of discontinuities andare thus optional, and in many cases the axial links and other axialconnector regions will be free from discontinuities, and remain intact.Thus, in many examples of the present invention, the scaffold willcomprise or consist of a plurality of axially linked circumferentialrings wherein the rings comprising or consisting of struts connected bycrowns where the separation regions are formed in only the struts andnot in the crowns (or crown region) or the axial links or other axialconnector regions. Placing the separation regions in the circumferentialrings, for example in struts and/or crowns, have the advantage ofproviding the ability to alter the circumferential properties of thestent at various time points after implantation. The circumferentialarrangement of the rings makes the ring structures critical for variousstent properties such as radial strength (flat plate), compositecompliance of the stented segment, further expansion to a largerdiameter after implantation, responding to vaso-dilatation, to name afew. For example, placing the separation regions in the circumferentialring structure provides the stent with altered, improved propertiesafter the discontinuities form following implantation. The needs forluminal stent are inherently time dependent and different at differentpoints in time. Over short period of time after implantation, the stentis required to have high radial strength to support the vessel open,then over the next period, after the tissue remodels and healing startsto occur or is completed, the requirement for high stent strength tomaintain the vessel open is no longer necessary, on the contrary, havinghigh strength may impair the physiological function of the vessel. Whilecurrent non-degradable (non-corrodible) stents such as stainless steelalloy stents, cobalt chrome alloy stents, and Platinum iridium alloystents, address the immediate initial high radial strength need of avessel, they typically do not respond to the changing vesselrequirements over time after implantation, wherein the vessel no longerrequires high radial strength to maintain the vessel open, and by havingsuch high radial strength maintained over time may irritate the vesseland cause further progression of disease or poor healing. A stent,preferably formed from non-degradable material (the stent can also beformed from degradable material), having separation regions within thestent rings which form discontinuities in the circumferential ringsafter implantation provide the stent with altered, improved propertiesafter the discontinuities form following implantation. Such stents ofthe present invention are configured to provide high initial radialstrength after expansion, where such high initial radial strength thendecreases over time after implantation, helping to address thephysiological needs of the vessel while maintaining the vessel open.Similarly, current non-degradable stents have low composite complianceof the stented segment “caging the vessel” typically for the life of thestent inhibiting the vessel natural vaso-motion ability, inhibiting thevessel's ability to respond to a vaso-dilator, or inhibiting the stentedsegment from expanding further to a larger diameter after implantation.The stent of the present invention having discontinuities formed withinthe circumferential rings following implantation may be configured tohave higher (or increased) composite compliance after expansion allowingthe stented segment of the vessel to respond to the natural variationsin blood pressure (vasomotion), allowing the stent (or the stentedsegment) to further expand after the initial expansion (and after inwardrecoil if any), and maintaining the vessel's ability to respond to avaso-dilator. The stent of the present invention may be configured tohave increased composite compliance in the stented segment shortly afterexpansion or after a longer period of time after implantation.

There are advantages of placing the separation regions in the strutsinclude they usually are lower stress regions of the ring and thussubject to less plastic deformation than the crowns. The location andsize of the struts may also offer additional options for more types ofseparation regions because they are typically larger and have lesstorque than some other area of a stent, such as the crowns or othercurved region of the ring. The struts typically can accommodate morechanges within it (such as having separation regions) without impairingthe function integrity of the stent, such as being able to expand thestent from a crimped configuration to an expanded configuration. Theorientation of the strut changes (opening) as the stent is expanded,allowing for separation regions designs configured to take advantage ofthe strut angle prior to deployment that is configured to keep theseparation region held together upon expansion of the stent, and openingthe struts to an angle in the expanded stent configuration that allowsfor the desired movement direction of the separated strut element suchas radial, circumferential, and/or axial movement.

There may be advantages to the placement of the separation regions inthe crowns. As a ring expands or contracts, the crowns are typicallysubject to high bending moments (torques), causing high stress andplastic deformation. Joining elements that are resistant to high moments(torques) can be advantageously used in the crown regions. The motion ofdeployment in the crown region causes a rotation between adjacentstruts. Joining elements that function to free this rotation, forexample through a ball and socket like joint or other joints as depictedthroughout the application, could lower the ring stiffness whilemaintaining cohesion between separable regions of the ring so that theymaintain a “tubular” overall shape, matching the lumen even afterseparation. Having separation regions within the crown (in the crown)can have a achieve higher composite compliance as maybe desired in someapplication. In addition, having separation regions in crowns may allowfor use of other material that were not suitable for stent applicationsdue to their limited mechanical properties such as elongation orbrittleness, where a separation region in the crown may allow forexpansion of the ring without breakage.

In said exemplary endoluminal prostheses, the struts may be joined bycrowns to define an angle between them, typically referred as an“included angle.” The included angle while the scaffold is in thecrimped configuration will typically be small or sometimes evennegative. The included angle will increase as the scaffold expands fromthe crimped configuration to an expanded stent configuration. Typically,the included angle in the crimped configuration of at least some strutsjoined by crowns ranges from −25° to +25°, more usually ranges from −15°to +55°. The included angle in the expanded configuration typicallyranges from 35° to 180°, more usually ranging from 45° to 150°. Whenpresent in struts, the separation region(s) can be located anywherealong a length of a strut, typically being located in or about a middleof the struts, typically bisecting the struts. Similarly, when presentin crowns, the separation region(s) can be formed at a point on thecrown, typically being located about a middle of the crown, e.g. alocation which bisects the crown which is typically a semicircle. In apreferred example, the separation region in the at least one strut is apre-formed break (or gap) bisecting the at least one strut into twoseparate elements. Examples of the separation regions in the at leastone strut include butt joint design, key and lock design, comb design,and/or other, wherein the bisected strut element adjacent to theseparation region may have various geometry, shape, dimensions, pattern,configured to have a uniform stent expansion, and/or maintain thestructural integrity of the stent upon expansion. The at least onebisected strut (separation region) is usually held together by one ormore material as described throughout this application.

In preferred examples, at least some of the separation regions arelocated on or in “low stress regions” of at least some circumferentialrings, i.e. those regions which experience less stress as the scaffoldis expanded, either by a balloon or by self-expansion, such as strutregions. As the scaffold expands from a crimped configuration to anexpanded configuration, the low stress regions, such as the struts, willexperience less stress than high stress regions, such as the crowns,which deform as the result of concentrated stress as the scaffoldradially expands. In a particular example, at least some circumferentialrings each having one or more separation regions have an initialstrength upon expansion of the stent in a physiologic environment, wherethe initial strength of at least some circumferential rings decreasesafter formation of discontinuities. In a preferred example, the one ormore separation regions are preferably located in struts, where thestruts undergo reduced (or minimal) stress as the scaffold is expandedfrom a crimped configuration to an expanded configuration, thusenhancing the structural integrity of the scaffolds during expansion byinhibiting all, or substantially all, formation of discontinuitiesduring expansion.

The separation regions in the scaffolds of the endoluminal prosthesesmay take a variety of forms. For example, the separation regions maycomprise a pre-formed break or gap in the crown region and/or in thestrut region), thereby bisecting the crown and/or strut structuralelement into two separate sections of said crown and/or said strut)which is joined by, covered by, or embedded in a material which willdegrade in the physiologic environment, typically a degradable polymerbut sometimes a degradable metal or metal alloy, with many specificexamples described in detail below. The degradable material comprisingon or more material, in turn, can be provided in a variety of forms andgeometries, including sleeves, coatings, solders, adhesives,laminations, and the like, which can be applied to at least one surfaceof the separation region, applied to at least one surface of the stent,applied to all separation regions surfaces, and/or applied to all stentsurfaces. In some examples, at least one surface, most, or all of aseparation region surface or a scaffold surface can be coated orlaminated with a degradable material. In a preferred example, thematerial fills all the space between opposed surfaces of a separationregion, and the stent abluminal, and luminal surfaces, and acts as anadhesive, glue, or attachment element, holding the surfaces together tomaintain the stent structural integrity upon expansion of the stent. Inother instances, the degradable material can be located on or in onlythe separation region and optionally a short distance on either sidethereof, e.g. 2 mm, 1 mm, 0.5 mm, or the like. In yet another example, anon-degradable material comprising one or more non-degradable materialcan additionally be applied to at least one separation region surfaceand/or additionally applied to at least one stent surface, and/oradditionally applied to all separation region surfaces and/oradditionally applied to all stent surfaces. The non-degradable materialcan be applied before the degradable material, or applied after thedegradable material. In a preferred example, the degradable and/or thenon-degradable material placed on the non-degradable stent are polymericmaterial. In another example, the polymeric material (degradable and/ornon-degradable) contains at least one drug. which may be coated on atleast one surface of the stent, preferably to cover at least theabluminal surface of the stent.

In a particular example, the degradable material can be applied by spraycoating, dip coating, sleeve encapsulating, printing, soldering, gluingwith an adhesive, or the like. The degradable material can be polymeric,metallic, or any other degradable material, as described in greaterdetail elsewhere herein. Typically, the degradable material hassufficient strength to hold the separation region together to immobilizeadjacent structural elements in a separation region while the scaffoldof the stent or other prosthesis is expanding from a crimpedconfiguration to an expanded configuration in a physiologic environment.The degradable material usually degrades after expansion of the stentfrom a crimped configuration to the expanded configuration. Thedegradable material may have a thickness that is substantially the sameas that of adjacent regions of the non-degradable structural elements,i.e. the degradable material will fill the gap or other space betweenthe adjacent structural elements but will not extend over these adjacentregions. In other examples, however, the degradable material may have athickness adjacent to said separation region, ranging from 5 μm to 30 μmthicker than the non-degradable structural elements thickness adjacentto said separation region, and may extend over said adjacent regions,may extend over, or cover, at least one surface of the stent, or maycovers all stent surfaces. The degradable material thickness can besubstantially the same for all separation regions or can have differentthicknesses, for example, to control timing of the formation ofdiscontinuities.

In preferred examples, the degradable material covers the non-degradablestructural elements of the stent substantially uniformly, i.e. havingsubstantially the same thickness over substantially all abluminalsurfaces of the structural elements and having the same thickness forsubstantially all luminal surfaces of the structural elements, but thedegradable material can also have different thicknesses for differentsurfaces of the scaffold structural elements. Typically, a coating orother cover over abluminal and/or luminal surface regions of thescaffold structural elements ranges from 3 μm to 50 μm, more usuallyranges from 5 μm to 30 μm. The degradable material may cover and/or fillthe separation region(s) only, may cover and/or fill the separationregion and surface(s) of adjacent structural element(s), may coverand/or fill the separation region as well as the surfaces of adjacentstructural element(s) and adjacent ring(s), or may cover the entirestent and fill all separation regions.

Some or all separation regions can be configured to form discontinuitiesat about the same time, or at different time periods, as describedelsewhere herein. In preferred examples, the degradable materialdegrades after a period ranging from 1 month to two years afterimplantation, preferably ranging from 2 months to one year afterimplantation, more preferably ranging from 3 months to 9 months afterimplantation.

In another preferred example, a non-degradable scaffold havingseparation regions held together by at least one degradable materialwill have an initial stent mean volume (or mean area) after expansionand after initial inward recoil after expansion if any, and wherein saidmean area (or mean volume) is from 0.75% to 0.90% of the initial stentmean volume (or mean area), substantially the same (maintained) initialmean stent volume (or mean stent area), or increased mean stent area (ormean stent volume), after degradation of said degradable material afterimplantation of the stent, and/or within a period ranging from 1 monthto 9 months after implantation, in a physiologic environment.

In another example, a non-degradable scaffold (or a stent), or otherprosthesis comprises a plurality of circumferential rings having one ormore separation regions along the path of each of said circumferentialrings. The scaffold has an initial strength, sufficient to maintain amean stent area (or mean stent volume) after expansion and after initialinward recoil (if any), and the scaffold after formation ofdiscontinuities exhibits a decrease in said initial strength whilesubstantially maintaining or increasing the stent mean area (or meanvolume), in a physiologic environment. Such non-degradable scaffoldstypically will have degradable material which can be stretchable(elastic), usually sufficiently stretchable (elastic) to hold structuralelements adjacent to separation regions together upon expansion of thescaffold, and/or sufficiently stretchable (elastic) to allow thescaffold, or a scaffold segment, to accommodate, or respond to,vaso-motion or vaso-dilatation after deployment, or after deployment andbefore degradation of the degradable material, or after degradation ofthe degradable material. The stent or other prosthesis in such examplesmay accommodate (or exhibit) an increase in diameter (or a change indiameter) in one or more scaffold segments (or in the stented segment)when a vaso-dilator is used, or when a change in pressure of about 180mmHg is applied. Such change in diameter ranges from 0.05 mm to 0.5 mm,more typically 0.7 mm to 0.4 mm, after expansion under physiologicconditions. In another example, the elastic material adjacent (includingin, on, around) at least one or more separation regions isnon-degradable material, such as a polymeric material, such aspolyurethane material. In a preferred example, the non-degradablematerial(s) have sufficient strength to contain the separation regiontogether upon initial deployment of the stent from a crimpedconfiguration to an expanded configuration, said elastic non-degradablematerial allowing the one or more rings or stented segment to furtherexpand and/or contract, after initial expansion of the stent, and/orafter formation of discontinuities, under physiologic conditions.

In yet another example, the separation regions may comprise an elasticmaterial disposed in, on, and/or adjacent to a gap, space, or otherbreak formed in a structural element of the ring, usually a strut,and/or a crown. The elastic material typically remains intact afterexpansion of the scaffold in the physiologic environment, and theelastic material may act as an “expansion joint” allowing expansion andin some cases contraction of the ring in order to increase radialcompliance under physiologic conditions. In some examples, suchexpansion joints will be immobilized by a bio absorbable material in theform of a coating, a sleeve, an adhesive, or any other form as describedelsewhere herein connecting or bonding or holding together adjacentseparated regions of the scaffold while the scaffold is being deployed.In other examples, the one or more expansion joints will not beimmobilized and the elastic material will provide sufficient strength toremain intact during balloon or other expansion while still providing adesired radial compliance or strength after expansion. The elasticmaterial in separation regions may be utilized alone, or in combinationwith other separation regions immobilized during balloon or otherexpansion by means such as degradable material.

In still other exemplary embodiments, the separation regions maycomprise “key-and-lock” junctions which are immobilized during expansionbut configured to separate after the initial expansion in thephysiologic environment. In some instances, the key-and-lock junctionsmay have combed interface surfaces that allow separation incircumferential and/or radial directions but which inhibit separation inan axial direction. In other instances, the key-and-lock junction willhave a smooth or straight interface surfaces that allows separation incircumferential, radial and/or axial directions. In other cases, thekey-and-lock junction will have non straight interface surface regionssuch as “saw”, “v”, “u”, inverted “v”, inverted “u”, or other surfaceregion interface, where such non straight surface region interface canhave or more surface region interfaces and where the one or more surfaceregion interfaces can have the same or different shapes, sizes,thickness, lengths, widths. Such key-and-lock junctions are typicallyimmobilized during expansion but configured to separate after theinitial expansion in the physiologic environment, for example beingcovered by, embedded in, or joined by a degradable material such as abiodegradable polymer.

In still other examples, the separation regions of the present inventionmay comprise a butt joint joined by, covered by, or embedded in thematerial which degrades in the physiologic environment.

The scaffolds of the endoluminal prostheses of the present inventionwill comprise a non-degradable material, typically a metal or a metalalloy material. The discontinuities forming in the metal scaffolds allowthe scaffolds to further expand after recoil from an initial expansion.The discontinuities will typically further allow the scaffold to furtherexpand to an expansion diameter larger than an initial expansiondiameter.

In some embodiments and examples, the circumferential rings may besubstantially perpendicular to a longitudinal axis of the scaffold inthe expanded and/or crimped configurations. In other embodiments andexamples, the circumferential rings may be inclined at an angle relativeto the longitudinal axis of the scaffold in one or both the expanded andcrimped configurations. In still further examples and embodiments,successive circumferential rings will be joined end-to-end in acontinuous helical pattern where each ring defines a single turn of thehelix.

In another aspect or example, the present invention provides a variablycompliant stent (or a controllable compliance stent, or an increasingcompliance stent), scaffold, or other luminal or valve prosthesiscomprising a non-degradable metal or metal alloy scaffold, such ascobalt chrome alloys, platinum iridium alloys, and stainless steelalloys, expandable from a crimped configuration to an expanded largerconfiguration. The scaffold has sufficient strength to support avascular lumen after expansion, preferably for at least a time periodafter expansion (or implantation) sufficient for the vessel to heal,and/or for at least a time period after expansion when the risk offurther, or additional, vascular lumen inward recoil (after any initialinward recoil of the stent following initial expansion) risk diminishesor is reduced, and/or for at least a time period ranging from 30 days to6 months after implantation, and/or for at least a time period rangingfrom 60 days to 6 months after implantation. The stent in some exampleshas an initial strength after expansion (or immediately after expansionor within 24 hours after implantation (expansion) or within 6 monthsafter implantation (expansion), or within 3 months after implantation orwithin two months after implantation), said initial strength beingsufficient to support a body lumen and where the stent is expanded inair or under physiologic conditions (such as water at 37° C.), thenunder physiological conditions, the initial strength decreases to asecond strength, lower than the initial strength, preferably decreasingwithin a period ranging from 3 days to 6 months, preferably said initialstrength decreases to a second lower strength in a period ranging from30 days to 6 months. The decrease in strength to said second strengthoccurs without mass loss, or without degradation of the non-degradablemetal or non-degradable metal alloy. The second lower strength in someexamples ranges from 10% to 100% of the initial strength, or ranges from10% to 90% of the initial strength, or ranges from 20% to 80% of theinitial strength, or ranges from 30% to 60% of the initial strength. Thestent in some other examples has an initial strength after expansion (orimmediately after expansion or within 1 hour after implantation(expansion) or within 2 hours after implantation, said initial strengthbeing sufficient to support a body lumen and where the stent is expandedin air or under physiologic conditions, then the initial strength underphysiological conditions increases to a first strength, larger than theinitial strength typically by 5% to 50%, preferably larger than theinitial strength by 10% to 30%, said first strength occurring afterinitial strength (or after initial strength measurement afterimplantation (expansion), or after one hour after implantation, or aftertwo hours after implantation, or between one hour after implantation andone month after implantation), wherein said initial strength increasesunder physiological conditions to a first larger strength then saidfirst strength decreases to a second strength, lower than the initialstrength under the same or similar physiological conditions, said firststrength preferably decreasing to below initial strength (secondstrength) within a period ranging from 15 days to 9 months, preferablysaid first strength decreases to the second lower strength (lower thaninitial strength) in a period ranging from 30 days to 6 months (orwithin a period ranging from 60 days to 6 months). The decrease instrength to said second strength being (or occurs) without degradationof the non-degradable metal or metal alloy (without mass loss). Thesecond lower strength in some examples ranges from 10% to 100% of theinitial strength, or ranges from 20% to 85% of the initial strength, orranges from 30% to 65% of the initial strength Immediately afterdeployment (or expansion), the scaffold has a composite compliance whenmeasured in the mock vessel (or a thin tube) of no greater than 1%,typically no greater than 0.7%, and often no greater than about 0.5%,typically being in a range from 0.1% to 1%, usually from 0.2% to 0.5%.After expansion under physiologic conditions (including simulatedphysiologic conditions) or after exposure to vascular conditions, thecomposite compliance or the stent compliance when measured in a mockvessel will increase to at least 1.2%, often to at least 1.5%, andsometimes to at least 2% or greater. In other examples of the variablycompliant stent prosthesis, the composite compliance of the stent whenmeasured in a mock vessel may increase by a factor of at least two,often at least three, and sometimes at least four, five, ten, or more,when compared to an initial composite compliance when measured in themock vessel.

Such variably compliant stent prostheses may have a variety of specificdesign features which provide the variable compliance. As described ingreater detail below, for example, the stent prostheses comprisingnon-degradable metal or metal allow scaffolds having separation regionswhich separate or form discontinuities, after exposure to vascularconditions for a threshold time. For example, some of the separationregions may be initially prevented from separating by a bioabsorbablematerial which degrades over time when exposed to vascular conditions.More specifically, the bioabsorbable material may be in the form of acoating, a sleeve, an adhesive, or any other form suitable for initiallyconnecting or bonding or holding together adjacent separated regions ofthe scaffold (or of the scaffold separated struts, or of the scaffoldseparated crowns, or of the scaffold separated structural elements)together. The bioabsorbable material may degrade over a time periodranging from 30 days to 3 years, often from 3 months to 2 years, andmore often from 3 months to 1 year when exposed to the vascularconditions. For purposes of determining whether the stent meets theseconditions, the stent may be exposed in vitro to vascular conditions(physiological conditions), as defined elsewhere herein' which areintended to mimic those conditions experienced when implanted in a humanblood vessel or lumen. It can also be tested after in vivo vascularconditions. It can also be tested using in vitro test under physiologicconditions as described in the application. In some other examples, oneor more rings containing one or more separation regions containnon-degradable material, preferably elastic material, preferablynon-degradable polymeric material. The non-degradable material can havesufficient strength to hold such separation region together uponexpansion of the stent, or together with another material (such as adegradable material, or other non-degradable material). The elasticnon-degradable material can provide for a desired radial complianceimmediately after expansion, or within 24 hours after expansion) such asresponding to use of nitroglycerin or another vaso-dilator by expandingone or more stent segments (or rings, or the stented segment) containingthe elastic material. The elastic non-degradable material in thisexample controls desired compliance, control further expansion afterinitial inward recoil, controls desired radial strength, and/or othermechanical properties of the stent, immediately after the initialexpansion, and/or within 30 minutes after the initial expansion (orimplantation), and/or within 24 hours after initial expansion(implantation). The stent can additionally comprise one or more rings(the same or different rings containing the separation regionscontaining the non-degradable elastic material) containing one or moreseparation regions, wherein the one or more additional separationregions contain degradable material (such as degradable polymericmaterial). The one or more separation regions containing thenon-degradable material typically inhibits forming discontinuities afterexpansion in physiologic environment but allow for the ring containingsaid separation region (or the stent segment) to have a desiredcompliance, or allows for further expansion after initial recoil afterinitial expansion, or allows for responding of the stented segment (orthe one or more rings) to a vaso-dilator, due to the stretching orelasticity of the non-degradable material. In yet another example, allor substantially all separation regions on one or more rings (or allseparation region contained on the stent) contain non-degradablematerial, wherein the non-degradable material inhibits formation ofdiscontinuities, but allows the stent (or the one or more rings) to havea desired compliance and/or radial strength, and or responding to avaso-dilator, due to the stretching of the material, elasticity, and/orother material property.

In other specific examples and embodiments, the non-degradable metal ormetal alloy scaffold may comprise regions reinforced with areinforcement material which degrades after exposure to vascularconditions for the threshold time period described above or elsewhere.The reinforcement material may comprise a bioabsorbable material whichdegrades over said time period. For example, the reinforcement materialmay fill voids in a crown and/or a strut of the non-degradable metal ormetal allow scaffold. Still further alternatively, the reinforcementmaterial may cover or coat at least a region of a surface of thenon-degradable metal or metal alloy scaffold.

In addition to displaying the variable compliance, as described aboveand/or elsewhere, the variably compliant stents of the present inventionwill display sufficient radial strength after expansion and implantationto hold the vascular lumen open and to inhibit or prevent vascularrecoil after initial recoil after initial expansion, for some minimumthreshold of time, usually at least 30 days, more usually at least 60days, and often at least 90 days or longer. Typically, for example for acoronary artery stent, the stent strength, measured using the flat platecompression of 10% test for example, (or the initial stent strength ofthe expanded stent) will be in the range from 0.030 Newton permillimeter of stent length to 0.14 Newton per millimeter of stentlength, particularly being from 0.04 Newton per millimeter of stentlength to 0.1 Newton per millimeter of stent length, and often beingfrom 0.05 Newton per mm of stent length to 0.1 Newton per millimeter ofstent length, preferably when such stent strength is measured, using theflat plate 10% compression, after the stent is expanded to nominal stentexpanded diameter. Usually, although not necessarily, the radialstrength of the stent (scaffold) will decrease (in some other example,the initial radial strength of the expanded stent increases to a firststrength larger than initial strength before decreasing to a secondstrength smaller than the initial expanded stent strength) afterexpansion and exposure to vascular conditions as the compositecompliance increases from an initial composite compliance (in some otherexample, the initial composite compliance decreases before increasing).The decrease in radial strength occurs concurrently (or correspondingly,or at a similar time, or at the same time, or approximately about thesame time) with the increase in radial compliance. In most cases, theradial compliance and the radial strength of the expanded stent willvary inversely to each other. Often, the radial strength of the stentscaffolds will decrease in a range from 20% to 100% of the initialradial strength which typically is measured immediately after expansionor shortly after expansion (such as within an hour, after expansion) andexposure to vascular conditions, sometimes decreasing in the range from20% to 80%, or in some cases, the initial radial strength of theexpanded stent increases before decreasing to substantially the initialstrength or to a lower strength than the initial strength while thecompliance increases from an initial compliance after implantation inphysiological conditions, or in some other cases the initial radialstrength of the expanded stent is substantially maintained while thecompliance increases after expansion in physiological conditions from aninitial compliance.

In a particular example or embodiment of the variably compliant stent,the non-degradable metal or metal alloy scaffold has a nominal expandeddiameter (the diameter to which the stent or other scaffold is intendedto be expanded by a balloon), and the strength and composite complianceare both measured after the stent has been expanded to a diameter whichis from 80% to 120% of the nominal expanded diameter. More commonly, thestrength and composite compliance will be measured when the stent hasbeen expanded to 100% of the nominal extended diameter.

In other examples, the stent has sufficient strength after deployment toan expanded configuration to support a body lumen, has inward recoilfrom 1% and 10% after deployment, and where the stent exhibitscompliance of 1% or larger than 1% after deployment, and/or having astent that has sufficient strength after deployment to support a bodylumen, and has an inward recoil from 1% to 10% after deployment to theexpanded configuration, and then where the stent exhibits outward recoilranging from 3% to 20% after deployment and after said inward recoil,under physiologic conditions, or under the use of vaso-dilators.

In some other examples, the composite compliance magnitude underphysiologic conditions (including vaso-dilator use) ranges from 0.05 mmto 0.5 mm, preferably ranges from 0.07 mm to 0.4 mm, more preferablyranges from 0.1 mm to 0.4 mm. The magnitude of such diameter changes aremeasured in one or more of the stented segment, or the mean of thestented segment), or preferably in a region about the middle of thestented segment.

In other examples, the stent outward recoil magnitude under physiologicconditions ranges from 0.05 mm to 0.5 mm, preferably ranges from 0.07 mmto 0.4 mm, more preferably ranges from 0.1 mm to 0.4 mm.

In another aspect or example, the present invention provides polymericprostheses with reinforcement elements and methods for their use andfabrication. An endoluminal prosthesis comprises a circumferentialscaffold patterned from a biodegradable polymer and having expansionregions which deform as the circumferential scaffold expands from asmall diameter configuration to a larger diameter configuration. In oneexample, the endoluminal prostheses of the present invention maycomprise coronary stent prosthesis. In another example, the endoluminalprostheses of the present invention may comprise a vascular stentprosthesis. In yet another example the stent prosthesis is anon-vascular stent prosthesis. Reinforcement elements are coupled to atleast some regions of the circumferential scaffold to stiffen thecircumferential scaffold after the scaffold has been expanded to thelarger diameter configuration. The reinforcement elements willpreferably be deformable and can be degradable (which also includescorrodible and erodible) or non-degradable (which also includednon-corrodible and non-erodible). In particular, the reinforcementelements may be malleable or elastic, may comprise metals and metalalloys, may comprise polymers, or may be formed in whole or in part fromother materials having mechanical properties that can reinforce theexpansion regions and/or other structures of the stent prosthesis asdescribed below or in this application.

The circumferential scaffolds in one example will typically comprisestent scaffolds of the type patterned from a tube or cylinder formed inwhole or in part from a biodegradable polymer. The tube or cylinder canbe formed by extrusion, dipping, spraying, molding, or printing. Thetube or cylinder of the biodegradable polymer will be patterned usingany one of many techniques well known in the art of forming stents frompolymers, such as laser cutting, photolithography, three-dimensionalprinting, stereolithography (SLA), and the like. The expansion regionswill typically comprise joints, hinges, crowns, curves, bends, and/ordeformable feature or structures or structural elements which may bejoined to adjacent struts, beams, or other less-deformable ornon-deformable features or structures or structural elements so thatexpansion region may open to increase an angle between the adjacent lessdeformable or non-deformable regions or structural elements, the strutsfor example, as the diameter of the circumferential scaffold is expanded(or is increased). Stents can also be formed from a wire (solid orhollow) or a fiber, and patterned or braided.

The reinforcement elements, for example, may be provided in order toimprove the stiffness, crush strength, crush resistance strength, radialstrength, hoop strength, or the like, of the circumferential scaffoldupon or after the scaffold has been expanded to the larger diameterconfiguration from a crimped configuration. In particular, the one ormore reinforcement elements may be coupled to one or more expansionregions and/or other region such as struts and/or links on thecircumferential scaffold in order to enhance such strength, particularlyas measured by a “plate” or “flat plate” test for example as commonlyknown in the art where the circumferential scaffold is placed betweenparallel, space-apart plates and a force needed to reduce the expandedscaffold diameter by a pre-determined amount (or % such as 10%compression force (N) or N/mm to normalize to stent length) is measured.Other type of tests to measure radial strength can also be utilized (andmeasured in psi for example) as commonly known in the art.

Most commonly in another example, the reinforcement elements will becoupled to at least some of the joints, hinges, crowns, bends, or otherexpansion regions so that such expansion regions, after expansion oropening, are better able to resist closing forces (or crushingresistance force) than they would be without the addition of thereinforcement elements. It will be appreciated that the expansionregions undergo deformation as the circumferential scaffold is expandedand that the presence of the reinforcement elements will open with theexpansion regions so that, once opened, the reinforcement elements willassist the scaffold to resist closure forces exerted by the blood vesselor other body lumen or body lumen lesions into which the scaffold hasbeen implanted. In addition to the deformable expansion regions thecircumferential scaffold will typically also include non-deformable orless deformable regions which usually retain or substantially retaintheir shape as the circumferential scaffold is expanded. Thereinforcement elements may also be coupled to at least some of thesenon-deformable or less-deformable regions. In many examples or mostembodiments, the expansion regions will be curved joints, crowns,hinges, bends, or the like, as described above, while the non-deformableregions will typically be struts, straight struts, or other usuallylinear elements of the scaffold, but sometimes may have non-linear orother shapes such as wave, S-, M-, V-, wavy liner, or wavy nonlinear,and U-shapes. Typically, expansion of the circumferential scaffolds ofthe endoluminal prostheses will be effected by inflatable balloons orother conventional apparatus, but in other cases the circumferentialscaffold could be fabricated from an elastic polymer or other materialand can be self-expanding where expansion is achieved by release of thecircumferential scaffold from constraint.

In one example, the reinforcement elements increase the stiffness orstrength of the reinforced region, the reinforced rings or expansionregions, and/or the stent.

In another example the reinforcement elements increase the strength ofat least one region of the stent by a range from 15% to 100%, preferablyincrease the strength by a range from 25% to 150%, more preferablyincreases the strength by a range from 25% to 200%.

In another example the reinforcement elements increase the strength ofthe stent by a range from 0.015 N/mm of stent length to 0.035 N/mm ofstent length, preferably increases the strength of the stent by a rangefrom 0.015 N/mm to 0.05 N/mm of stent length, more preferably increasethe strength of the stent by a range from 0.015 N/mm to 0.09 N/mm ofstent length, when measure using flat plate test 10% compression. Forexample, the strength (using flat plate test method for example) of0.015 N/mm for a 3.0 mm stent by 28 mm stent length equates to 0.015N/mm times 28 mm (stent length) which equals to 0.42N strength.

In another example the stent having reinforcement elements has astrength ranging from 0.03 N/mm to 0.06 N/mm of stent length, preferablyhas strength ranging from 0.025 N/mm to 0.07 N/mm of stentlength, morepreferably has a strength ranging from 0.025 N/mm to 0.09 N/mm of stentlength, when measuring strength using flat plate test 10% compression.For example, a 0.03 N/mm stent length strength (using flat plate testfor example) for a 3.5 mm diameter stent by 18 mm stent length equatesto 0.03 N/mm times 18 mm of stent length which equals 0.54N.

In another example, the reinforcement elements decrease initial inwardrecoil (or recoil after expansion or recoil after deployment) ordecrease subsequent inward recoil (recoil after implantation, or recoilafter procedure completion, or recoil within 30 days from implantation,or recoil within 6 months from implantation, or recoil afterimplantation initial recoil and 6 months' time period, or recoil afterimplantation initial recoil and 1 day, or recoil after implantationrecoil and 30 days).

In another example, the reinforcement elements decrease the inwardrecoil of the stent to a range from 1% to 10%, preferable to a rangefrom 1% to 7%, more preferably to a range from 1% to 5%, afterimplantation. In another example, the reinforcement elements decreasethe subsequent inward recoil of the stent to a range from zero to 5%,preferably to a range from zero to 3%, more preferably to a range fromzero to 2%, at the various time points discussed.

In another example, the stent having reinforcement elements has aninward recoil ranging from 1% to 10%, preferable ranging from 1% to 7%,more preferably ranging from 1% to 5%, after expansion or deployment. Inanother example, the stent having reinforcement elements has subsequentinward recoil ranging from zero to 5%, preferably ranging from zero to3%, more preferably to a range from zero to 2%, most preferably saidstents have substantially zero inward subsequent recoil (or said stentsubstantially maintain the initial recoil after implantation), at thevarious time points discussed.

In another example, at least some reinforcement elements are coupled toat least some expansion regions on at least some rings of the stent,wherein the stent expands from a crimped configuration to an expandedlarger configuration, and wherein the reinforcement elements providesufficient strength in the expanded stent configuration to support abody lumen.

The reinforcement elements in one example may be coupled to thecircumferential scaffold in a large variety of patterns. Thereinforcement elements may be attached to some or all of the expansionregions while not necessarily being attached to any of thenon-deformable or less deformable regions. In particular, thereinforcement elements may be attached to one, two, three, or more ofthe expansion regions of the scaffold or scaffold ring. In some examplesor embodiments, the reinforcement elements are attached to all of theexpansion regions of the scaffold or scaffold ring, and in otherpreferred examples or embodiments, the reinforcement elements areattached to all but one of the expansion regions of the scaffold orscaffold ring. In other examples or embodiments, the reinforcementelements may be attached to both expansion regions as well as to some orall of the non-deformable or less-deformable regions. In other examplesor embodiments, the reinforcement elements may be attached to at leastsome expansion regions extending at least partially into thenon-deformable or less-deformable regions. In other examples orembodiments, the reinforcement elements may be attached to at least someexpansion regions extending to at least a mid-point of thenon-deformable or less-deformable regions length. In other examples orembodiments, the reinforcement elements may be attached to at least someexpansion regions extending substantially the entire length of thenon-deformable or less-deformable regions. The reinforcement elementsmay be embedded (fully or partially) into the material of thecircumferential scaffold, for example being embedded into at least someof the expansion regions (or embedded into any of the surface regions ofthe expansion regions such as abluminal surface region, luminal surfaceregion, and/or side surface regions). Alternatively, the reinforcementelements in another example may be attached or otherwise disposed on thescaffold so that they lie at least partly on an exterior of least someof the expansion or non-deformable regions.

The reinforcement elements can be coupled to the stent prosthesis(including or comprising embedded, attached, or disposed on) afterpatterning the stent, where the coupling of the reinforcement elementsto the patterned stent regions is performed by a variety of ways such aspress fitting the reinforcement element onto the stent or stent region,creating or pre-forming a groove or a space or a slot by a variety ofmeans such as laser or mechanical or chemical means and then pressfitting the reinforcement elements onto the stent or stent region,dissolving the polymer material partially or softening the material topress fit or insert, to contain the reinforcement element, and/oradhesively attaching the reinforcement elements to the patternedstructure surface or region (such as polymeric structure) to name fewmethods. Alternatively, the reinforcement elements can be coupled to thestent before patterning such as coupled to the tube (such a polymerictube) from which the stent is patterned, and wherein the tube andreinforcement elements are patterned together (or separately) to form apatterned stent using the methods discussed above and/or throughout theapplication and the patterning means discussed in the application suchas laser patterning. The reinforcement elements can also be formed withthe tube (such as polymeric tube) that forms the stent using dipping,spraying, or molding for example, or the reinforcement element is one ormore wires (solid or hollow) that is patterned or woven into a stent, orthe reinforcement elements can be a wire (solid or hollow) encapsulatedby a material (such as the main polymer material) and is woven orpatterned into a stent. The reinforcement elements are coupled aspieces, solid wire, tube, or patterned structure. The reinforcementelements are coupled to the stent structure (such as the polymeric stentmaterial) while having discontinuities or separation regions beforecoupling to the stent prosthesis as described in this application touncage the lumen and/or allow scaffold or lumen enlargement, or thediscontinuities or separation regions are formed onto the reinforcementelements (through a variety of means such as laser cutting, dissolving,cutting, etc.,) after coupling to the stent, wire, or tube, and then thediscontinuities or separation regions are reconnected or held togetherby means such as adhesives, main polymer, different polymer, sleeve, orother means that holds the stent structural element together uponexpansion from a crimped configuration to an expanded largerconfiguration.

Typically, stents including the circumferential scaffolds will comprisea plurality of adjacent rings where the expansion regions comprisecurved, bent, hinged, jointed, crowns, or other regions of the ringswhich straighten or open as the scaffold is radially expanded. Mosttypically, such rings will be sinusoidal, serpentine rings, zig-zagrings, diamond (Palmaz-type) rings, or any other type of radiallyexpandable stent ring known in the vascular stent art, including opencell design, closed cell design, or combination, or other known to oneskilled in the art. Usually, individual rings will be oriented in planeswhich are oriented perpendicularly to a central axis, or perpendicularto a longitudinal axis, of the circumferential scaffold in the crimpedor expanded configuration. In other embodiments or examples, however,the planes of the rings or expansion regions or circumferentialstructural elements can be inclined at an angle relative to the scaffoldlongitudinal axis (e.g. from 1° to 85°, or from 1° to 45°, or from 10°to 75°, or from 25° to 75°, or usually from 5° to 15°), and in somecases, the “rings” or expansion regions or circumferential structuralelements may be formed in a helical structure, or joined in a continuoushelical arrangement. The individual rings, or adjacent turns of ahelical stent structure, may be axially joined together by axial linksbetween hinges, crowns, beams, struts and/or other components of therings or turns. In other example, the scaffold can be formed from a wire(solid or hollow in at least some regions) and patterned into a stent,where adjacent rings are connected in one or more locations (orregions). In one example stents comprising rings having an orientationranging from being perpendicular to the longitudinal axis of the stent,to having an angle to such longitudinal axis of the stent ranging from1° to 85°, to having a helical configuration ring pattern, wherein atleast some rings have at least one separation region. In some otherexample, a stent, such as a valve containing stent, can comprise one ormore circumferential rings (or one or more circumferential structuralelements). In such example, the stent comprises one or more separationregions, hinges, or other structures as described in this application.In a particular preferred example, the stent comprises one or morecircumferential rings, wherein the one or more rings comprise aplurality of struts joined by crowns. Usually, every two struts arejoined by a crown, or every crown joins two struts, on a ring. At leastsome, preferably all rings are joined to adjacent rings by at least oneaxial link, or by joining one or more crown regions (using solder,adhesive, or fusing of the material) of adjacent rings.

The reinforcement elements in one example may be disposed in segmentsabout the rings, or alternatively may be disposed to extend aroundsubstantially an entire circumferential length of at least some of therings. The reinforcement element(s), however, will be configured to haveor form at least one break, discontinuity, or separation region, intheir circumferential direction or length so that the reinforcementelements can circumferentially separate or/and uncage, or incrementallyexpand after deployment as the blood vessel or other body lumen remodelsduring the healing process. In this way, the reinforcement elements willbe able to provide a desired initial strength and resistance to collapseduring deployment and/or an initial period after deployment, but willnot constrain or inhibit the scaffold from uncaging and/or expanding,and/or the blood vessel/lumen from expanding after the biodegradablepolymer (such as the main polymer) of the circumferential scaffold hassoftened, and/or the polymer's molecular weight has decreased, and/orthe polymer has degraded, and/or the polymer has at least partly eroded(including degraded or corroded) leaving the reinforcement elements(which have not eroded or not fully eroded) free to further expand inresponse to vessel remodeling or other physiologic conditions.

The circumferential scaffolds of the present invention may include someor all conventional features found in the patterns of conventionalstents. For example, the stent patterns may include axial links whichhold adjacent rings together to form closed-cells of a type well knownin the stent arts. In such cases, the reinforcement elements for examplemay be coupled to at least some of the axial links, in which cases aplurality of individual reinforcement elements may together form boxstructures which are coupled to substantially parallel rings as well assubstantially parallel axial links. In one example the reinforcementelement is coupled to at least one axial link has at least one break.

The reinforcement elements in one example can be individual pieceshaving the shape or geometry, or substantially having the shape orgeometry, or having smaller shape or geometry, or having larger shape orgeometry, or having different shapes or geometry, from the structuralelement to be coupled to such as crowns, struts, and/or links. Examplesof shapes include square, round, rectangle, triangle, semicircle, andother shapes. In these examples the pieces are discontinuous or discretepieces (either in contact or not with other adjacent reinforcementelements). The pieces can have deburred end regions, rounded endregions, ball end region, or other types or geometries to preventinflammation after the polymeric material has degraded and or resorbed.In a preferred example, substantially all of the expansion regions of atleast some rings have reinforcement elements pieces coupled to saidexpansion regions wherein the reinforcement elements pieces spansubstantially the entire expansion regions segment or at least part ofthe expansion regions segment. In another example, substantially all ofthe expansion regions of at least some rings have reinforcement elementspieces coupled to said expansion regions wherein the reinforcementelements pieces span the entire expansion regions segment and extend atleast partially into the non-deformable or substantially non deformable(such as struts) segments. In a preferred example, the reinforcementelements, the reinforcement elements pieces' shape and/or geometrygenerally substantially mimic or contour to the shape and/or geometry ofthe structural elements to be coupled to. The reinforcement elementspieces in one example can be larger size in at least one dimension,smaller size in at least one dimension, or the same size in at least onedimension to the structural element the pieces are coupled to.Reinforcement elements pieces coupled to at least some structuralelements of a biodegradable material allow the stent to further expand,and/or allows the stent to uncage, and/or allows the vessel to exhibitvaso-motion or vaso-dilation, after implantation (or after expansion orafter deployment) under physiologic conditions (and/or through theintroduction of therapeutic agents such as nitro) while stiffening orstrengthening the stent upon expansion of the stent to support a bodylumen.

In another example, the reinforcement elements can be one or morereinforcement elements segments coupled to at least some rings and/orother structural elements such as a link. For example, a reinforcementelement segment is coupled to (or spans) one crown and one strut on aring, and/or coupled to (or spans) one crown and one strut on a ring,and one link, and/or coupled to (or spans) multiple crowns and struts ona ring, and multiple links. In another example, the reinforcementelements segments form a pattern on the stent, said pattern is usuallysymmetrical pattern (but can also be non-symmetrical pattern), saidpattern can be a variety of shapes including closed patterns and openpattern. When the reinforcement element segment span the entirestructural elements of a ring crowns and/or struts, said reinforcementelement segment would have at least one break or discontinuity in saidcrowns and/or struts (said break or discontinuity is formed before orafter coupling to said structural element) to allow the stent to furtherexpand after degradation of the polymeric material, or to allow thestent to uncage, or to allow the vessel to have vaso-motion, or to allowthe vessel to have vaso-dilation, after expansion (or after deployment),under physiologic conditions (and/or through the introduction oftherapeutic agents such as nitro), said reinforcement elements segmentstiffens or strengthens the stent, by having sufficient strength tosupport a body lumen after deployment.

In another example, the reinforcement elements can be one or morereinforcement elements segments coupled to at least some rings (orcircumferential structural elements), or coupled to substantially allrings (or circumferential elements). When the reinforcement elements, orreinforcement element segment spans the entire ring length (orcircumferential structural element) without breaks, discontinuities, orseparation region, or spans more than one ring entire lengths withoutbreaks, discontinuities, or separation regions, or when thereinforcement elements span substantially the entire stent withoutbreaks, discontinuities, or separation regions, said reinforcementelement(s), or reinforcement element segment(s) would have at least oneor more regions along the circumferential path for each ring (crowns orstruts for example), and/or one or more crown regions along thecircumferential path of each ring, and/or one or more strut regionsalong the circumferential path of each ring, wherein the one or moresaid region contain a reinforcement element (or one or morereinforcement elements) having a cross sectional area ranging from 200micron squared to 4000 micron squared, preferably a cross sectional arearanging from 400 micron squared to 3000 microns squared, more preferablya cross sectional area ranging from 700 micron squared to 2500 micronsquared, wherein the one or more said regions allow the said one or morerings, and/or the stent, to further expand after degradation of thepolymeric material (or metallic degradable material), and/or allow thestent to uncage, and/or allow the vessel to have vaso-motion, and/orallow the vessel to have vaso-dilation, and/or allow the stent to haveradial strain ranging between 1% and 5% at 3.0 mm expanded diameter,after stent expansion (or after deployment), under physiologicconditions (and/or through the introduction of therapeutic agents suchas nitro), said reinforcement elements segment stiffens or strengthensthe stent, by having sufficient strength to support a body lumen afterdeployment. In another example, the said region having said crosssectional area above spans substantially the entire length of at leastsome rings, or substantially spans the entire stent. In another example,the said region having said cross sectional area spans at least somerings, or spans substantially all rings, but does not span at least someaxial links. In another example, the said regions having said crosssectional area, wherein the reinforcement element width ranges from 10%to 50% of the width of the structural element at said region, preferableranges from 20% to 40%, more preferably ranges from 25% to 35%. Inanother example, the said regions having said cross sectional area,wherein the reinforcement element thickness ranges from 10% to 70% ofthe thickness of the structural element at said region, preferableranges from 20% to 50%, more preferably ranges from 30% to 40%. Inanother example, the one or more regions having said cross section areawherein the ratio of thickness to width of the structural elements 1.5:1to 3:1, and wherein the ratio of the structural element at said one ormore regions thickness to width ranges from 0.7:1.4, preferably rangesfrom 0.8:1. In a preferred example of this example, the reinforcementelement is non-degradable metal or metal alloy, and the stent framematerial (which the reinforcement element is coupled to) is a polymericdegradable material. In another preferred example of this example, thereinforcement element is a non-degradable metal or metal alloy and thestent frame material is a degradable metal or metal alloy. The stent inthis example containing reinforcement elements and having a degradableframe material has sufficient strength to support a body lumen whenexpanded from a crimped configuration to an expanded configuration, andwherein the stent radial compliance increases after expansion while thestrength of said stent decreases after expansion. In another example,the stent radial strain increases after degradation of the degradablepolymeric material and wherein the initial strength after expansiondecreases after degradation of the polymeric material. In anotherexample of this example, the reinforcement elements combined with thedegradable frame stent material, have sufficient strength to support abody lumen, wherein the reinforcement elements alone does not havesufficient strength to support a body lumen. In another example of thisexample, the reinforcement elements combined with the degradable framestent material, have sufficient strength to support a body lumen,wherein the reinforcement elements alone, or the stent frame materialalone, do not have sufficient strength to support a body lumen.

In another example, the stent having reinforcement elements, bridgingelements, separation regions, breaks, and other features described inthis application exhibit increase in radial strain (or compliance) afterexpansion and decrease in radial strength after said expansion. Inanother example, said increase of radial strain (or compliance) anddecrease in strength, begins (or occurs) from a period ranging from oneweek after expansion of the stent to 9 months after expansion of thestent, preferable begins one month after expansion to 6 months afterexpansion, more preferably begins 2 months after expansion to 6 monthsafter expansion.

Most commonly, the reinforcement elements will comprise anon-degradable, usually being a metal (including metal alloy), moreusually being a malleable metal which can be opened and deformedtogether with the circumferential scaffold but which has a higherstrength to resist closure after the scaffold has been partially orfully expanded. In other examples, however, the reinforcement elementsmay be a polymer which has a higher stiffness than the main polymer (orthe degradable patterned polymer or the polymer the reinforcementelements are coupled to at least in part) of the circumferentialscaffold. Polymeric reinforcement elements may be formed from the sameor different polymers than those which form the circumferentialscaffold. When the reinforcement elements are formed from the samepolymer, the reinforcement element polymer will typically have a highermolecular weight and/or higher crystallinity, or will otherwise be astiffer polymer than that of the main body polymer (or the degradablepatterned polymer or the polymer the reinforcement elements are coupledto at least in part) of the circumferential scaffold, the reinforcementpolymer in this example can be degradable or non-degradable. In yetanother example, the reinforcement elements can also comprise adegradable metal (which includes metal alloys) such as magnesium and/ormagnesium alloys.

In yet another example, a stent prosthesis comprising a biodegradablepolymeric material where the polymeric degradable material degrades in 1months to 5 years, preferably degrades in 2 months to 3 years, morepreferably degrades in 3 months to 2 years, wherein reinforcementelements are coupled to at least some expansion regions of at least somerings of said stent. The reinforcement elements can be non-degradable ordegradable material, metal or metal alloys, polymers (degradable ornon-degradable), or other material, that stiffens (or strengthens) saidexpansion regions (or stent) in the stent expanded configuration.Typically, the polymeric material degrades faster than the reinforcementelements, but can also (the polymeric material) be configured to degradeat the same time (or rate) as the reinforcement elements, or slower thanthe reinforcement elements. In another example the reinforcementelements do not degrade or corrode.

In yet another example, a stent prosthesis comprising a biodegradablemetallic material such as magnesium alloy where the metallic degradablematerial degrades in 1 months to 5 years, preferably degrades in 2months to 3 years, more preferably degrades in 3 months to 2 years,wherein reinforcement elements are coupled to at least some expansionregions of at least some rings of said stent in accordance of any of theexamples of this application. The reinforcement elements can benon-degradable or degradable material, metal or metal alloys, polymers(degradable or non-degradable), or other material, that stiffens (orstrengthens) said expansion regions (or stent) in the stent expandedconfiguration. Typically, the metallic material degrades faster than thereinforcement elements, but can also (the metallic material) beconfigured to degrade at the same time (or rate) as the reinforcementelements, or slower than the reinforcement elements. In another examplethe reinforcement elements do not degrade or corrode.

In still other examples, the reinforcement elements may be formed froman elastic metal or polymer (including spring and/or shape memory likeNiTi). For example, for reinforcement elements which are curved or bentto conform (or contour) to a joint or hinge or an expansion region onthe polymeric or metallic circumferential scaffold, the reinforcementelement will typically be in a closed or constrained configuration whencoupled to the corresponding hinge or joint on the circumferentialscaffold in the crimped configuration. In this way, the typically metalreinforcement element will act to help open and/or keep open thecircumferential scaffold as it is balloon expanded or self-expanded toits larger diameter configuration. Moreover, even after implantation inthe blood vessel or other body lumen, the elastic, shape memory, and/orspring-like reinforcement elements will typically still be at leastpartially constrained by a polymer (such as the main polymer) or metalso that they will continue to bias the circumferential scaffold to openat least in the region where they are coupled to while simultaneouslyenhancing the strength and crush-resistance of the deployed prosthesissuch as endoluminal prostheses themselves and/or through otherreinforcement elements with high stiffness disposed on the same,adjacent, or other expansion regions or structural elements of saidcircumferential scaffold. Optionally, the scaffold may have additionalmetal, polymer, or other non-elastic (malleable) reinforcement elementscoupled to same or other expansion regions, e.g. hinges or joints, onthe circumferential scaffolds. For example, as one or more polymerscomprising the scaffold or rings (such as main polymer) thereof start tosoften, and/or degrade, and/or start to decrease in a molecular weight,and/or as the blood vessel or other body lumen heals and remodels overtime, the elastic reinforcement elements will be able to continue toprovide an opening bias to enhance enlargement of the scaffold. Themagnitude of the opening bias is controlled by the elastic (includingspring, shape memory) material properties and/or processing, and/orcontrolled by the degradation of the polymeric material (such as mainpolymer) containing the reinforcement elements. The terms stent andscaffold are used interchangeably in this application. In anotherexample, the typically metallic shape memory or spring reinforcementelement having two ends can be coupled to adjacent struts(non-deformable or substantially non-deformable structural elements)wherein the reinforcement element is configured as an expansion regionconnecting the two adjacent struts (along the length of the struts),where the reinforcement element expansion region is in the crimpedconfiguration when the stent is in the crimped configuration, andwherein the reinforcement element expansion region expands as the stentexpands to the deployed configuration. The reinforcement elementscontinue to push open (increasing the angle between said adjacentstruts) after deployment of the stent (after the stent inward recoilsfrom the deployed configuration). The reinforcement elements furtherexpand the stent after deployment. The reinforcement elements areattached or coupled to the structural elements as described throughoutthis application. In one example, the reinforcement elements furtherexpand the stent prosthesis by a mean range from 0.05 mm to 1 mm, from0.1 mm to 0.5 mm, preferably from 0.1 mm to 0.3 mm, or correspondingmean cross sectional areas, after stent deployment and after stentrecoil. In another example, the reinforcement elements increase thestent mean diameter or mean cross sectional area by a range from 2% to15%, preferably 3% to 10%, of the stent mean expanded diameter or meancross sectional area, after stent deployment and stent inward recoil).In another example, stent prosthesis comprises a non-degradable shapememory alloy comprising NiTi or other type material, the stent has oneor more separation region (and/or one or more hinges), and wherein thestent expands from a crimped configuration to an initial expandedconfiguration and wherein the one or more separation region (or hinges)form discontinuities (or allow the stent to have radial displacement),allowing the stent to respond to a vaso-dilator, or contours to achanging lumen (or annulus) configuration.

In a preferred example the degradable polymeric stent comprisingdegradable main polymer (the polymer forming substantially the polymericscaffold structure, or the polymer forming substantially a continuousscaffold structure, or the polymer forming substantially a scaffoldstructure without separation regions, or the polymer forming thescaffold structure except for at least some separation regions ordiscontinuities). The degradable polymeric stent can comprise more thanone polymer in addition to the main polymer (adjacent, blended, mixed,etc.). Reinforcement elements are preferably non-degradable metal andmetal alloys, having higher crush resistance (strength) compared to themain polymer or other additional polymers, such reinforcement elementsare coupled to at least some regions of the scaffold structural elementssuch as crowns and/or struts, wherein the reinforcement elements haveseparation regions or discontinuities allowing the stent to uncageand/or expand in a physiological environment. The reinforcement elementscan also be polymers (degradable or non-degradable) or corrodible metaland metal alloy.

In a preferred example, the reinforcement elements can have a variety ofshapes and geometries including rod (or solid) or hollow wire, circular,semi-circle, triangle, rectangle, square, oval or other shapes andgeometries. In a preferred example, the cross sectional area of at leastsome structural elements (such as crowns and/or struts) containing orcoupled to the reinforcement elements, have the reinforcement elementsrepresenting 5% to 90% of the cross section area of said structuralelement, preferably represent 10% to 75% of the cross section area, morepreferably represent 15% to 75% of the cross section area of saidstructural element. The structural element can be fully embedded in thestructural element, partially embedded, or attached to one or moresurface regions of the structural element, as described in thisapplication.

In another example or aspect of this invention, a stent comprises abiodegradable polymeric material (or biodegradable metallic material)patterned into a structure comprising structural elements where at leastone crown region (preferably at least some crown regions, morepreferably at least half of the crown on the at least some rings),and/or at least one strut region (preferably at least some strutregions, more preferably at least ¼ of the struts regions on the atleast some rings), are not formed (or are partially formed), on at leastsome rings, and said regions are formed or replaced with reinforcementelements, preferably non-degradable reinforcement elements preferablymetallic such as CoCr alloys, Stainless steel alloys, or other metal ormetal alloys, or can also be non-degradable polymeric reinforcementelements. The polymeric stent is formed (or formed with the region whichis then removed) in one example without the at least one crown regionand/or without the at least one strut region, on at least some rings,and where the metallic reinforcement elements having substantially thesame size (or preferably smaller size) compared to adjacent polymericcrown regions and/or strut regions, and the reinforcement elements areshaped (or bent or curved) into a crown region shape and/or a strutregion shape, and the reinforcement elements crown region two ends areattached to the strut end regions of the not-formed crown. The two endsof the reinforcement elements can be attached to the two strut ends ofthe polymeric stent as a butt joint and adhesively bonding the twomaterials together at the junction, and/or containing both reinforcementelement and polymeric material junction region with a sleeve, and/orforming a slot in each of the polymeric stent two strut end regions(during laser patterning or after) and inserting or press fitting thereinforcement element crown region ends into the formed slots,optionally adhesively bonding an overlap region (for example 0.05 mm to1 mm overlap region) of the two materials and/or containing the overlapregion with a sleeve (where the sleeve can extend beyond the overlapregion), and/or creating or having a slot formed in the reinforcementelement end regions where the polymeric ends press fit into, to hold thereinforcement elements and the polymeric material junction together, orto hold the butt joint together, during expansion from a crimpedconfiguration to expanded larger configuration. Similarly, reinforcementelements can connect to not-formed polymeric strut ends (or partiallyformed struts) as discussed above. The reinforcement elements stiffenthe expansion region and/or the non-deformable or substantially nondeformable regions in the expanded stent configuration. The stent isexpandable from a crimped configuration to an expanded largerconfiguration and have sufficient strength to support a body lumen. Inone example, the stent polymeric biodegradable material degrades from 3months to 3 years, while the non-degradable reinforcement elementsremain in the vessel wall. The stent after deployment, uncages thevessel, exhibits vaso-motion, exhibits vaso-dilation, exhibitsvaso-constriction, and/or further expands to a larger configuration,and/or has radial strain ranging from 1% to 10%, preferably rangingbetween 1% to 7%, more preferably ranging from 1.5% to 7%, underphysiologic conditions. The stent in one example comprises degradablepolymeric material comprising structural elements comprising crowns andstruts where at least some of the crowns and/or struts have been notformed, detached, or removed after forming (such as mechanically such ascutting them or chemically such as using solvents or other material toremoving them), and replaced with non-degradable metallic reinforcementelements. The stent is formed from polymeric tube or formed fromfilaments that are patterned into a stent, or other methods known to oneskilled in the art. The reinforcement elements can be formed from a tubeor a wire and shaped or patterned into the shape of the structuralelement it would be replacing such as crown. In one example thereinforcement elements are formed from a patterned tube and thencomponents of said patterned tube are removed (mechanically for example)and inserted (or attached) into the location of the not formed polymericstructural element (to replace it in one example). In another example awire reinforcement element is shaped into the structural element to bereplaced and attached. Other methods of forming the structural elementscan include a variety of ways such as forming a pattern flat sheet,injection molding, or other. The shapes and sizes of the reinforcementelements can vary and is discussed throughout the application in moredetail.

In another example, a biodegradable metallic stent such as magnesiumalloy stent is patterned into a structure comprising structural elementswhere at least one crown region (preferably at least some crown regions,more preferably at least half of the crown on the at least some rings),and/or at least one strut region (preferably at least some strutregions, more preferably at least ¼ of the struts regions on the atleast some rings), are not formed (or are partially formed), on at leastsome rings, and said regions are formed or replaced with reinforcementelements, preferably non-degradable reinforcement elements preferablymetallic such as CoCr alloys, Stainless steel alloys, or other metal ormetal alloys, or can also be non-degradable polymeric reinforcementelements. The metallic stent is formed (or formed with and then removed)in one example without the at least one crown region and/or without theat least one strut region, on at least some rings, and where themetallic reinforcement elements having substantially the same size (orpreferably smaller size) compared to adjacent metallic stent crownregions and/or strut regions, and the reinforcement elements are shaped(or bent or curved) into a crown region shape and/or a strut regionshape, and the reinforcement elements crown region two ends are attachedto the strut end regions of the not-formed crown. The two ends of thereinforcement elements can be attached to the two strut ends of themetallic stent as a butt joint and adhesively bonding the two materialstogether at the junction, and/or containing both reinforcement elementand metallic stent junction region with a sleeve, and/or forming a slotin each of the metallic stent two strut end regions (during laserpatterning or after) and inserting or press fitting the reinforcementelement crown region ends into the formed slots, optionally adhesivelybonding an overlap region (for example 0.05 mm to 1 mm overlap region)of the two materials and/or containing the overlap region with a sleeve(where the sleeve can extend beyond the overlap region), and/or creatingor having a slot formed in the reinforcement element end regions wherethe metallic stent structural element ends press fit into, and/or laserwelding (or fusing) the two material, to hold the reinforcement elementsand the metallic stent junction together, or to hold the butt jointtogether, during expansion from a crimped configuration to expandedlarger configuration. Similarly, reinforcement elements can connect tonot-formed metallic stent strut ends (or partially formed struts) asdiscussed above. The reinforcement elements stiffen the expansion regionand/or the non-deformable or substantially non deformable regions in theexpanded stent configuration. The stent is expandable from a crimpedconfiguration to an expanded larger configuration and have sufficientstrength to support a body lumen. In one example, the stent metallicbiodegradable material degrades or substantially degrades in a period oftime ranging from 3 months to 3 years, while the non-degradablereinforcement elements remain in the vessel wall. The stent afterdeployment, uncages the vessel, exhibits vaso-motion, exhibitsvaso-dilation, exhibits vaso-constriction, and/or further expands to alarger configuration, and/or has radial strain ranging from 1% to 10%,preferably ranging between 1% to 7%, more preferably ranging from 1.5%to 7%, under physiologic conditions. The stent in one example comprisesdegradable metallic material comprising structural elements comprisingcrowns and struts where at least some of the crowns and/or struts havebeen not formed, detached, or removed after forming (such asmechanically such as cutting them or chemically such as using solventsor other material to removing them), and replaced with non-degradablemetallic reinforcement elements. The stent is formed from a metallictube or formed from filaments (or wires) that are patterned into astent, or other methods known to one skilled in the art. Thereinforcement elements can be formed from a tube or a wire and shaped orpatterned into the shape of the structural element it would be replacingsuch as crown. In one example the reinforcement elements are formed froma patterned tube and then components of said patterned tube are removed(mechanically for example) and inserted (or attached) into the locationof the not formed metallic stent structural element (to replace it inone example). In another example a wire reinforcement element is shapedinto the structural element to be replaced and attached. Other methodsof forming the structural elements can include a variety of ways such asforming a pattern flat sheet, injection molding, or other. The shapesand sizes of the reinforcement elements can vary and is discussedthroughout the application in more detail.

In another aspect or preferred example, it is desirable to a have asstent comprised from a non-degradable high strength material, such asmetallic material, in order to have sufficient strength upon deploymentof the stent in a body lumen (in some cases a degradable material suchas degradable metallic material having high crush resistance can also beused for this example, such materials tend to degrade slowly caging thevessel for a long time). However, such stents cage the vessel or segmentadjacent to the stent and prevent one or more of the following fromoccurring potentially reducing the utility, safety, and/or effectivenessof the stent: uncaging the vessel or stented segment, exhibitingvaso-dilation within or spanning the stented segment, exhibitingvaso-constriction within or spanning the stented segment, exhibitingfurther enlargement of the stent, exhibiting radial strain over thestented segment in the range from 1.5% to 5%, after deployment. In orderto solve or address on or more of the previous needs, the non-degradablemetallic stent, such as L605 CoCr alloy stent, is configured bypatterning into a structure comprising structural elements where atleast one crown region (preferably at least some crown regions, morepreferably less than half of the crowns on the at least some rings),and/or at least one strut region (preferably at least some strutregions, more preferably at least ¼ of the struts regions on the atleast some rings), are not formed (or are partially formed, or areformed and then removed), on at least some rings, and said regions areformed or replaced with degradable bridging elements, such as degradablepolymeric material (for example PLLA based polymers) or such asdegradable metallic material (for example magnesium alloy). Thenon-degradable metallic stent is formed (or formed with and thenremoved) in one example without the at least one crown region and/orwithout the at least one strut region, on at least some rings, and wherethe degradable bridging elements having substantially the same size (orpreferably smaller size, but can also be larger size) compared toadjacent metallic stent crown regions and/or strut regions, and thedegradable bridging elements are shaped (or bent or curved) into a crownregion shape and/or a strut region shape and/or the shape of the stentstructural elements they are replacing, and the degradable bridgingelements crown region two ends are attached to the strut end regions ofthe not-formed crown. The two ends of the degradable bridging elementscan be attached to the two strut ends of the metallic stent as a buttjoint and adhesively bonding the two materials together at the junction,and/or containing both degradable bridging element and metallic stentjunction region with a sleeve, and/or forming a slot in each of themetallic stent two strut end regions (during laser patterning or after)and inserting or press fitting or fusing or melting the degradablebridging element crown region ends into the formed slots, optionallyadhesively bonding an overlap region (for example 0.05 mm to 1 mmoverlap region) of the two materials and/or containing the overlapregion with a sleeve (where the sleeve can extend beyond the overlapregion), and/or creating or having a slot formed in the larger sizedegradable bridging element end regions where the metallic stentstructural element ends press fit into, and/or laser welding (or fusing)the two material, to hold the degradable bridging elements and themetallic stent junction together, or to hold the butt joint together,upon expansion of the stent, or during expansion of the stent from acrimped configuration to expanded larger configuration. Similarly,degradable bridging elements can connect to not-formed metallic stentstrut ends (or partially formed struts) as discussed above. Thedegradable bridging elements are less stiff, or substantially less stiffand therefore weakens the expansion region, and/or the non-deformable orsubstantially non deformable regions in the expanded stentconfiguration. However, the degradable bridging elements provide for oneor more of the following benefits: provide continuity of thecircumferential structural element (such as rings) at least uponexpansion (or for a period of time after expansion) which helps thestent to uniformly expands (or improve expansion uniformity), providefor drug release in said region to inhibit neo-intimal hyperplasia,provide for partial or full expansion of the stent circumferential ringin the said expansion region, provide for lesion coverage and minimizeplaque pro-lapse, provide for temporary scaffolding and then uncaging ofthe stent and/or vessel as the degradable bridging elements degrade orcorrode in a period ranging from 1 months to 4 years, preferably rangingfrom 3 months to 4 years, provide support to the vessel wall. The stentis expandable from a crimped configuration to an expanded largerconfiguration and have sufficient strength to support a body lumen, Thenon-degradable stent structural elements remain in the vessel wallsubstantially intact in one example (or substantially held together, orsubstantially in place, in one example). The stent after deployment,uncages the vessel, exhibits vaso-motion, exhibits vaso-dilation,exhibits vaso-constriction, and/or further expands to a largerconfiguration, and/or has radial strain ranging from 1% to 10%,preferably ranging between 1% to 7%, more preferably ranging from 1.5%to 7%, under physiologic conditions (and/or through introduction oftherapeutic agents such as nitro). The stent in one example comprisesnon-degradable metallic material comprising structural elementscomprising crowns and struts where at least some of the crowns and/orstruts have not been formed, or have been detached, or have been removedafter forming (such as mechanically removed such as cutting them orchemically removing them such as using solvents or other material toremoving them or to melt them), and are replaced (or formed) withdegradable bridging elements in said regions. The stent is formed frommetallic tube, metallic sheet, or formed from filaments (or wires) thatare patterned into a stent, or formed using other methods known to oneskilled in the art. The degradable bridging elements can be formed froma tube or a filament/wire and shaped or patterned into the shape of thestructural element it would be replacing such as crown for example. Inone example the reinforcement elements are formed from a patterned tubeand then components of said patterned tube are removed (mechanically forexample) and inserted (or attached or press fitted) into the location(or region) of the not formed metallic stent structural element. Inanother example a filament degradable bridging element is shaped intothe structural element shape replace and attached the ends as described.Other methods of forming the degradable bridging elements can include avariety of ways such as forming a pattern from a flat sheet and usingcomponents from the sheet to replace the not formed structural element,injection molding of said degradable bridging elements, or other. Theshapes and sizes of the degradable bridging elements can vary (smaller,same, or larger, than the replaced structural element) as discussedthroughout the application in more detail.

In one example, the bridging elements are degradable. In another examplethe bridging elements are non-degradable but provides for one or more ofthe objectives of this invention. The bridging elements can also be asuture (or wire) tying both ends of the structural element that is notformed, or that is modified or removed partially or completely. Thesuture can tie both ends of the structural element through a holeadjacent to each end of the structural element where the suture (orwire) is threaded through the holes and tied forming a continuity of thenot formed structural element (said suture or wire bridging two crownsor two struts for example).

In another example, the bridging elements can be formed from shapememory material or spring material (which can also be reinforcementelements in other examples), where the bridging elements help bias openat least some crowns to expand further after implantation.

In another example, the non-degradable metallic stent (such as CobaltChrome alloy L605 or MP35 for example) comprises a wire (round orsubstantially round, or oblong, or other shapes), where the wire ispatterned into a stent. The stent comprises structural elementscomprising a plurality of rings, each ring comprises crowns and struts.At least one strut and/or at least one crown, on at least some rings,are removed. The ends of the stent where the strut and/or crowns wereremoved are treated to create a hollow space in the wire. A degradablebridging element is inserted in the hollow space at each of the ends ofthe wire stent to bridge the gap of the removed strut and/or crown.Optionally an adhesive, or degradable sleeve are applied to thejunctions or overlap further reinforcing the junction segment so thatthe junction is held together as the stent expands from a crimpedconfiguration to an expanded larger configuration. In another example,the degradable bridging elements are treated to create a hollow space,where the stent wire structural element is inserted or press fittedinto. Optionally an adhesive or sleeve are applied to further hold thejunction together.

In another example, the stent prosthesis is formed as a tube where thetube comprises a non-degradable material layer (such as cobalt chromealloy layer) that is either sandwiched between, on top of, or on thebottom of a magnesium alloy layer. The tubing is patterned into a stent.At least some regions on at least some rings (or at least some crownregions, and/or strut regions, on at least some rings) have thenon-degradable material (such as the cobalt chrome alloy layer)substantially removed by laser, chemical means, or mechanical means, toprovide the stent to uncage after expansion under physiologicalconditions. The stent prosthesis in another example can be formed as asheet where the degradable layer is on top or bottom of thenon-degradable material, the stent is patterned and processed asdescribed above. The sheet is rolled and attached (or fused) forming apatterned stent.

In another example, the stent prosthesis is formed as a wire where thewire comprises a non-degradable material layer (such as cobalt chromealloy layer) on top, or on the bottom of a degradable polymeric ormetallic material layer (such as magnesium alloy layer or PLLA basedpolymer). The wire is patterned into a stent. At least some regions onat least some rings (or at least some crown regions, and/or strutregions, on at least some rings) have the non-degradable material (suchas the cobalt chrome alloy layer) substantially removed (formingdegradable bridging elements connecting the two ends of thenon-degradable structural element, by laser, chemical means, ormechanical means, to provide the stent to uncage after expansion underphysiological conditions, preferably uncaging as the degradable materialdegrades.

In another example, the stent prosthesis is formed as a tube where thetubing comprises a non-degradable material layer (such as cobalt chromealloy layer) that is on top or inside of a degradable polymeric materiallayer (such as PLLA based polymer layer). The tubing is patterned into astent. At least some regions on at least some rings (or at least somecrown regions, and/or strut regions, on at least some rings) have thenon-degradable material layer (such as the cobalt chrome alloy layer)substantially removed by laser, chemical means, or mechanical means, toprovide the stent to uncage after expansion under physiologicalconditions. The stent prosthesis in another example can be formed as asheet where the degradable layer is on top or bottom of thenon-degradable material, the stent is patterned and processed asdescribed above. The sheet is rolled and attached (or fused) forming apatterned stent.

In one example of any of the examples in this application, the stent istested, or deployed (expanded) under one or more of the followingconditions: in air, in water bath, in water bath at 37° C., underphysiologic conditions, in a pulsating (or contracting) environment,under administration of one or more agents that causes vaso-dilation orvaso-constriction of the stented segment, in a tube, in a vessel, in abody lumen, under a pressure difference (gradient) ranging from 100 mmHgto 200 mmHg, under pressure difference (or magnitude) of 100 mmHg, underpressure difference (or magnitude) of about 176 mmHg, or underconditions to test compliance or strength as described in thisapplication, or any other condition described in this application. Insome cases, all of the conditions described in this paragraph arereferred to as physiologic conditions.

In one example, physiologic conditions comprises one or more of: inambient air, in water bath, in water bath at about 37° C., at about 37°C. environment, in a radial strain tester (compliance tester), in afatigue tester, in a pulsating environment, in a pressure or pressuredifferential environment, in a pulsating environment approximatelysimulating body lumen or body organ environment, administration oftherapeutic agents such as vaso-dilators, or vaso-constrictors, in acontracting and/or expanding environment, in a body lumen, in a bodyvessel, in a body annulus, or other.

In a preferred example, the stent prosthesis further comprises at leastone coating on at least one surface of the stent prosthesis. The coatingin one example contains at least one drug, preferably an m-torinhibitor. In another example the stent prosthesis comprises at leastone drug. In another example, the stent prosthesis comprises at leasttwo drugs, an m-tor inhibitor, and a vaso-dilator. In yet anotherexample, the at least one coating degrades at a rate slower than thedegradable (polymeric or metallic) material rate of degradation. Inanother example, the at least one coating degrades at a rate faster thanthe degradable material rate. In yet another example, at least onecoating covering at least one surface of the non-degradable stent. Inyet another example, at least one degradable coating covers at least onesurface of the non-degradable stent. In yet another example, at leastone degradable coating covers at least one surface of the non-degradablestent, and at least one non-degradable coating covers at least onesurface of the non-degradable stent.

In one example, the stent prosthesis exhibits, provide, or is configuredto do one or more of the following: uncaging the stent, uncaging thestented segment of the lumen or vessel, uncaging at least somecircumferential structural elements (rings) of the stent, uncaging atleast some rings of the stent, uncaging the vessel or vessel wall,exhibiting vaso-motion, exhibiting vaso-dilation, exhibitsvaso-constriction, further expansion of the stent to a largerconfiguration after implantation, and/or the stent has composite radialstrain (or compliance) ranging from 1% to 10%, preferably rangingbetween 1% to 7%, more preferably ranging from 1.5% to 7%, underphysiologic conditions (and/or through introduction of therapeuticagents such as nitro). The stent prosthesis in this example exhibits orprovides the one or more properties described above (uncaging etc.) inone or more of the following stent states: as formed, as patterned,after treatment or processing after forming (or patterning) of thestent, as the stent is deployed, upon deployment of the stent, uponexpansion of the stent, and/or after deployment or expansion of thestent, in a body lumen for example. The stent prosthesis in this exampleexhibits or provides the one or more properties described above(uncaging, etc.) in (or over) one or more of the following: at leastsome circumferential structural elements, at least some rings,substantially all circumferential structural elements, substantially allrings, at least some regions, spanning substantially the entire stent orthe entire stent segment, the stent region, and/or the stent segment.

In one example of any of the examples, the bridging elements can alsobridge at least one link (or link region), in addition to bridging oneor more structural elements (such as struts and/or crowns) on at leastsome rings.

In another aspect of this invention, or another example, anon-degradable (such as metal (including alloy) but can also bepolymeric) stent prosthesis comprises structural elements, saidstructural elements in one example comprise a plurality of rings, eachring comprises struts and crowns, and each ring is connected to anadjacent ring in at least one location (or region). At least one strut(or part of a strut, or a strut region ranging) and/or at least onecrown (or part of a crown, or a crown region), on at least some ringsare not-formed (or removed after forming), forming a gap (ordiscontinuity) between said remaining crown ends (or remaining crownregions) and/or between remaining strut ends (or remaining strutregions), wherein the gap magnitude ranges from 1 microns to 3 mm,preferably ranges from 2 microns to 2 mm, more preferably ranges from 3microns to 1 mm, when said gap is measured as a straight line betweenthe remaining struts and/or remaining crowns in the expanded stentconfiguration (or in the crimped stent configuration). The ends of theremaining struts and/or crowns can be configured to have different,preferably larger dimensions, geometry, and/or surface area than anadjacent struts and/or crown, and can have various shapes such as round,square, semi-circle, rectangle, etc. In one example, at least some ringshave at least one gap (or discontinuity) along said rings. In anotherexample, at least some rings have at least three gaps (ordiscontinuities) along said rings. In yet another example, at least somerings have from 1 to 3 gaps (or discontinuities). The stent prosthesisis expandable from a crimped configuration to an expanded largerconfiguration and have sufficient strength to support a body lumen. Thestent in a preferred example has a substantially uniform expansion. Thestent in another preferred example has a maximum circular diameter of0.7 mm to 1.5 mm in the gap region. The stent in a further preferredexample has sufficient coverage to inhibit (or minimize) smooth musclecell proliferation. The stent prosthesis exhibits, provide, or isconfigured to do one or more of the following: uncaging the stent,uncaging at least some circumferential structural elements of the stent,uncaging at least some rings of the stent, uncaging the vessel or vesselwall, exhibiting vaso-motion, exhibiting vaso-dilation, exhibitsvaso-constriction, further expansion of the stent to a largerconfiguration after implantation, and/or the stent has radial strainranging from 1% to 10%, preferably ranging between 1% to 7%, morepreferably ranging from 1.5% to 7%, under physiologic conditions (and/orthrough introduction of therapeutic agents such as nitro). The stentprosthesis in this example exhibits or provides the one or moreproperties described above (uncaging etc.) in one or more of thefollowing stent states: as formed, as patterned, after treatment orprocessing after forming (or patterning) of the stent, as the stent isdeployed, upon deployment of the stent, upon expansion of the stent,and/or after deployment or expansion of the stent, in a body lumen forexample. In a preferred example, the not formed (or removed) strutand/or crown remaining end region is connected to the same or adjacentstructural element provided that such connection does not complete thegap (or discontinuity) of said ring and the gap in said ring remainsdiscontinued.

In another example, the stent prosthesis comprises a plurality of ringscomprising struts and crowns, where at least one strut and/or crownregions on at least some rings are severed (or cut) during laserpatterning for example but can also be done mechanically, or othermethods. The severed region is deburred and/or shaped into a geometry tobe atraumatic and/or to create a contact, and/or to maintain a contact,and/or to substantially hold the cut region substantially together, toallow expansion of the stent prosthesis from a crimped configuration toan expanded larger configuration and have sufficient strength to supporta body lumen. The stent in a preferred example have a substantiallyuniform pattern in the expanded configuration. The cut end regions canbe abutting, overlapping, or have a temporary holding means, in thecrimped configuration, to allow deployment into an expandedconfiguration, or to allow the stent to have a substantially uniformpattern in the expanded stent configuration, and/or to allow for asubstantially sufficient coverage to support a body lumen.

During laser cutting, patterning, or other formation of the separationregions and discontinuities in the scaffold, portions of the partiallyformed scaffold may be temporarily together so that the structure doesnot prematurely separate after the discontinuities are formed and beforethe discontinuities are immobilized by gluing, coating, sleeveformation, or the like. For example, after a tubular member is laser cutor otherwise patterned to form circumferential rings including strutsand crowns, the ends of the tubular member may be temporarily held byholding fixtures positioned at each end of the scaffold. In particular,one, two, three, or more terminal crowns at each end of the scaffold maybe formed to have holding features, such as enlarged ears or similarfeatures that can be grasped by the holding fixtures. In this way, theholding fixtures will hold the partially formed scaffold together as theseparation regions are formed, e.g. by first cutting or bisecting astrut and/or crown in one or more of the circumferential rings and thencoating the entire scaffold in a biodegradable sleeve to hold the stenttogether so that it may be removed from the fixtures and subsequentlydeployed.

In another example, a non-degradable (such as metal (including alloy)but can also be polymeric) stent prosthesis comprises circumferentialstructural elements, said structural elements comprises in one example aplurality of rings, each ring comprises struts and crowns, and each ringis connected to an adjacent ring in at least one location. At least somerings are configured (patterned and/or treated for example) to have agap (or discontinuity) in said rings. For example, the stent can bepatterned to have wherein the gap magnitude ranges from 1 microns to 3mm, preferably ranges from 2 microns to 2 mm, more preferably rangesfrom 3 microns to 1 mm, when said gap is measured as a straight line tocomplete (or connect or provide continuity) said rings. In a preferredexample, the maximum circular inter-strut (or inter-ring or betweenrings) distance in the region where the gap is ranges from 0.9 mm to 2mm, preferably ranges from 1 mm to 1.5 mm In one example, at least somerings have at least one gap (or discontinuity) along said rings. Inanother example, at least some rings have at least three gaps (ordiscontinuities) along said rings. In yet another example, at least somerings have from 1 to 3 gaps (or discontinuities). The stent prosthesisis expandable from a crimped configuration to an expanded largerconfiguration and have sufficient strength to support a body lumen. Thestent in a preferred example has a substantially uniform expansion,sufficient vessel coverage to inhibit SMC proliferation. The stentprosthesis exhibits, provide, or is configured to do one or more of thefollowing: uncaging the stent, uncaging at least some circumferentialstructural elements of the stent, uncaging at least some rings of thestent, uncaging the vessel or vessel wall, exhibiting vaso-motion,exhibiting vaso-dilation, exhibits vaso-constriction, further expansionof the stent to a larger configuration after implantation, and/or thestent has radial strain ranging from 1% to 10%, preferably rangingbetween 1% to 7%, more preferably ranging from 1.5% to 7%, underphysiologic conditions (and/or through introduction of therapeuticagents such as nitro). The stent prosthesis in this example exhibits orprovides the one or more properties described above (uncaging etc.) inone or more of the following stent states: as formed, as patterned,after treatment or processing after forming (or patterning) of thestent, as the stent is deployed, upon deployment of the stent, uponexpansion of the stent, and/or after deployment or expansion of thestent, in a body lumen for example.

In one example, the stent prosthesis where at least some rings have atleast one gap (or discontinuity) on each said ring. In one example, theregion (or end region) of the structural elements (ring) where the gapis (or where the gap begins or ends) can be free (not connected to anystructural element, or any adjacent structural element), or can beconnected to other structural elements such as connected to a strut,and/or crown, (or can be connected to other adjacent structural elementssuch as connected to a strut, and/or crown) at the end region, oradjacent to the end region, or anywhere along the structural elementleading to said end region. The connection to said region can besubstantially straight connection, and/or a crown connection, and/orother connection having a variety of shapes, dimensions, and/orgeometries from said region to other structural elements (or adjacentstructural elements). Examples of connection (including connectionshapes) include Z, S, M, U, W, Y, L, or other type connection. Thedimension of said connection can be different or substantially the sameas other adjacent structural elements. The connections can also belarger or smaller in width and/or thickness in other examples. Theconnections shapes and/or dimensions can be substantially the same ordifferent on at least some rings.

In another example, the stent prosthesis comprises structural elementscomprising a plurality of rings, each ring comprises struts and crowns,and each ring is connected to an adjacent ring in at least one region.At least some rings have at least one region between two crown and/orbetween two struts, configured (patterned or otherwise) to have twostruts (or two strut regions) and/or two crown (or two crown regions)where the two strut regions and/or crown regions overlap over somelength. The struts and/or crowns are connected at opposite ends, whilethe other end region forms a discontinuity in said ring. The strutsand/or crowns free end region can have various shapes and geometry torestrain or hold together the stent prosthesis upon deployment of thestent. The strut and/or crown regions can also have grooves or othershapes to hold the restrain the sliding struts and/or crowns uponexpansion of the stent prosthesis. The stent prosthesis is typicallyexpandable from a crimped configuration to an expanded largerconfiguration and has sufficient strength to support a body lumen. Thestent allows the body lumen to uncage upon deployment. The stent hassufficient structural elements surface region coverage (thickness,width, and/or geometry) in the discontinuity region to support a bodylumen.

In one example of any of the examples in this application, a stentprosthesis comprising circumferential structural elements, wherein thestructural elements comprise struts and crowns, and wherein the stent isconfigured (for example patterned and/or treated) to allow the stent tobe expandable from a crimped configuration to an expanded largerconfiguration, and wherein the stent has sufficient strength in theexpanded configuration to support a body lumen, said stent prosthesisuncages, and/or has radial strain (or compliance) ranging between 1% and5%, and/or further expands, as formed, upon expansion, and/or afterexpansion, in a body lumen (or under physiologic condition and/or undertherapeutic condition such as introduction of nitroglycerine). Examplesof said stent prosthesis comprise one or more from the examplescomprising reinforcement elements, bridging elements, separationregions, struts and/or crowns having gap regions, or other. Said stentprosthesis can be degradable, non-degradable, metallic (includingalloys) or polymeric, over a period ranging from 3 months to 5 yearsunder physiologic condition. The stent prosthesis in an example can beformed from a tube and patterned into a stent or formed from one or morewires (or filaments) and patterned into a stent. The stent can also beformed from a flat sheet and rolled to form a stent. The flat sheet canbe patterned before rolling it to form a stent or the flat sheet can berolled to form a tube and then patterned. In one example thecircumferential structural elements comprise a plurality of rings eachring comprising crowns and struts having one or more of theconfigurations described in this application. In another example thestructural elements comprise crowns and struts having one or morediscontinuities allowing the stent to uncage as formed, and/or furtherexpands, as formed, upon deployment, and/or after deployment.

In another example of any of the example in this application, at leastsome struts and/or crowns have at least one separation region,discontinuity, or break. In another example, at least some struts and/orcrowns have at least two separation regions, discontinuities, or breaks,on said struts and/or crowns. In still further examples, at least someof the struts and/or crowns will be free from separation regions. Instill further and often preferred examples, at least some struts willhave separation regions while all crowns in a circumferential ring willbe free from separation regions. It has been found that locatingseparation regions in struts which normally do not deform duringexpansion is preferable to locating separation regions in crowns whichdeform as the scaffold expands.

In another aspect or in another example, the present invention providesnon-degradable or slowly degradable prostheses material havingstructural elements such as circumferential elements and/or rings withseparation regions and/or environmentally responsive separation regions.By “environmentally responsive,” it is meant that the separation regionswill separate, become void from material such as a degradable polymermaterial, create a gap, open, break, allow for movement in one or moredirection, and/or degrade, in response to physiologic conditions whichincludes vascular conditions, and/or other luminal conditions, and/or inresponse to being placed in water at ambient temperature or at 37° C.,and/or in response to being placed in a buffered solution, and/or insaline, and/or in response to the physiologic conditions (e.g. thevascular or luminal conditions), and/or the physiologic pressure, towhich the scaffold is exposed to such as after implantation in the bloodvessel or other body lumen, and/or in response to the scaffold beingexposed to pressure ranging from 30 mmHg to 200 mmHg, preferably rangingfrom 40 mmHg to 120 mmHg, more preferably ranging from 50 mmHg to 80mmHg, and/or in response to the scaffold being exposed to pulsatingpressure ranges from 30 mmHg to 150 mmHg, preferably pulsating pressureranges from 30 mmHg to 120 mmHg, and more preferably pulsating pressureranges from 30 mmHg to 90 mmHg, or in response to therapeutic agentssuch as vaso-dilators or vaso-constrictors introduction.

The stent in a preferred example in any of the examples in thisapplication can uncage, can uncage in at least some circumferentialcross sections or regions, uncages over the stent segment, and/or expandto a larger diameter (or configuration) in physiologic conditions(includes physiologic environment) in at least some circumferentialcross sections or regions of the stent prosthesis. The larger stentdiameter can be larger than the deployed diameter and/or larger than thediameter of the stent after recoil from the deployed expandedconfiguration. The stent diameter in response to said pressures and/orpulsating pressure (as described in this application) in one examplechanges and/or increases from expanded and/or deployed diameter (afterrecoil if any from said expanded and/or deployed diameter) to a largerdiameter permanently or temporarily while exposed to the pressure and/orpulsating pressure, the stent diameter changes and/or increases rangesfrom 0.045 mm to 1 mm, preferably ranges from 0.05 mm to 0.6 mm, andmore preferably ranges from 0.06 mm to 0.3 mm, or changes from 0.1 to0.3 mm. The stent radial strength after deployment, in the same exampleor other example, ranges from 12 psi to 30 psi, preferably ranges from13 psi to 25 psi, more preferably ranges from 15 psi to 25 psi. Thestent flat plate strength (10% crush) after expanding the scaffoldand/or after deployment, in the same example or a different example,ranges from 0.03 N/mm stent length to 0.95 N/mm stent length, preferablyranges from 0.035 N/mm stent length to 0.9 N/mm stent length, morepreferably ranges from 0.0.04 N/mm stent length to 0.085 N/mm stentlength. The scaffold inward recoil after expansion of the scaffoldand/or after deployment in the same example or a different exampleranges from 1% to 10%, preferably ranges from 2% to 7%, more preferablyranges from 2% to 5%. The stent inward recoil preferably remainssubstantially the same after deployment. The stent prosthesis preferablyexpands further to a larger configuration after introduction of avaso-dilator in the body. The stent preferably has radial strain (orcompliance) in the expanded configuration ranging between 1% and 5%. Inthe same example or a different example, the non-degradable stent radialstrength after deployment decreases by at least 25%, decreases by atleast 50%, decreases by at least 75%, decreases by 100% of the scaffoldinitial radial strength upon deployment. The period of time in the sameexample or a different example where the strength decreases ranges from1 day to 2 years, preferably ranges from 1 month to 1 year, morepreferably ranges from 2 months to 9 months, more preferably ranges from3 months to 9 months. In the same example or a different example, thenon-degradable stent radial strength after deployment (initialdeployment) decreases by a range from 0% to 25% within 30 days from suchinitial deployment radial strength, and/or decreases by a range from 10%to 50% within 90 days from such initial deployment radial strength,and/or decreases by a range from 25% to 90% within 180 days from suchinitial deployment radial strength, and/or decreases by a range from 50%to 100% within 270 days from such initial deployment radial strength.The non-degradable stent in this example further comprises at least onedegradable polymer, and further comprises at least one drug. In apreferred example the at least one drug is contained in a polymer. Inanother example or in addition to the previous example, the stentcomprises at least one non-degradable polymer. In yet another example orin addition to the previous examples, the stent further comprisesradiopaque markers (degradable or non-degradable).

In a preferred example throughout this application after deployment,there is uncaging of the stent, and further expansion of the stent afterdeployment, lumen enlargement, and other properties of the stent and/orlumen comprising one or more of the whole stent or lumen, at least onepart or region of the stent or lumen, at least one circumferential crosssection or region of the stent or lumen, or at least somecircumferential cross sections or regions of the stent or lumensegments, or the stented segment.

In another example, the present invention provides non-degradableprosthesis material having circumferential elements and/or rings withseparation regions. Separation regions are regions that havediscontinuity as formed, and/or as patterned (including afterpatterning), and/or after processing or treatment, and/or beforeimplantation, and/or after implantation, and/or after implantation inphysiologic conditions. Discontinuity includes completely and/orsubstantially one or more of the following: being separate, becomingvoid from material, having a gap, forming a gap, open, having a break,forming a break, unlocking, un-touching, un-contacting, removal ofmaterial between separation regions or adjacent to separation regions,removal of material holding separation regions together, ability ofseparation region to move in one or more directions, and/or degrade. Inthis example, the stent has sufficient strength upon deployment tosupport a body lumen, and wherein the stent after deployment may recoilto a smaller configuration before further expanding to a largerconfiguration (larger than the recoil configuration and/or larger thanthe deployed expanded configuration). The stent can expand to the largerconfiguration in a body lumen and/or under physiologic condition. Inanother example the stent uncages, or uncages at least in some regionsand/or rings, or the stented segment.

In another example, one or more circumferential rings containing one ormore separation regions may contain at least one or more non-degradablematerial (such as a non-degradable polymeric material) wherein saidmaterial inhibits forming a gap or other discontinuity. The one or morecircumferential rings containing separation regions comprising anon-degradable material are configured to expand to a larger diameter orcross-section after initial expansion (and recoil if any), due to theelasticity and stretching of the non-degradable material underphysiological conditions in response to vascular pulsation and/orexpansion in response to a vaso-dilator agent. In this way, one or morerings and typically the entire stented segment exhibits a desiredcompliance after implantation under physiological conditions. Thenon-degradable material in such embodiments and examples typically hassufficient elasticity to continuously expand and/or contract underphysiologic conditions including systolic pulsation of the blood vessel.

In yet another example, one or more separation regions comprisingnon-degradable materials may still form a gap or other discontinuityafter the initial expansion, preferably after a period ranging from 30days to one year after the initial expansion. Although non-degradable,the material may deteriorate or fatigue over time and/or underphysiologic conditions and thus allow the separation regions toseparate, to form gaps or other discontinuities.

In yet another example, the one or more separation regions may beconstrained by one or more non-degradable material, such as a polymericsleeve or a polymeric coating, wherein the one or more of the separationregions after formation of gaps or other discontinuities remainconstrained by the non-degradable material even after formation of gapsor other discontinuities. The non-degradable material, formed as asleeve or coating for example, can also cover one or more rings of thestent, cover one or more stent surfaces, or can cover the entire stentsurface. The sleeve or coating constraining the separation regions allowthe one or more rings or the stented segment) to have a desiredcompliance, further expand after initial recoil, and/or respond to anintroduction of a vaso-dilator.

In another example, an endoluminal prosthesis according to this and/orone aspect of the invention and/or a preferred example comprises ascaffold having structural elements such as circumferential elementsand/or rings patterned from a non-degradable material, such as anon-degradable metal, metal alloy, or hard non-degradable plastic, wherethe scaffold is configured to expand from a crimped configuration to anexpanded configuration and the scaffold has sufficient strength in theexpanded configuration to support a body lumen. At least some of thecircumferential elements and/or rings will have at least one separationregion configured to form discontinuities in the circumferential elementand/or ring soon or immediately after deployment (initial deployment),and/or over time, and/or after an initial expansion in a physiologicenvironment, and/or after exposure to one or more of the otherconditions disclosed in this application. Such discontinuities allow thescaffold or at least some circumferential cross sections of the scaffoldto further expand to a larger configuration in at least, preferably tofurther expand after an initial recoil which may occur after deployment,more preferably to further expand beyond the initial expansion, mostpreferably allowing the scaffold to uncage or uncage in at least somecircumferential cross sections or regions of the stent, preferablyuncage in the circumferential direction. That is, after the scaffold hasbeen initially deployed by a balloon or in some instances byself-expanding from constraint, the discontinuities allow portions ofthe scaffold to move apart and the rings to expand, preferably togetherwith luminal expansion, more preferably together with luminal expansionas a result of luminal remodeling. In one example, the ring separationregions may be present in crowns regions, hinge regions, and/or strutregions. The stent preferably responds to vaso-dilation stimuli byenlarging the lumen in the stented segment. The stent preferably hascomposite radial strain (or compliance) ranging from 1.5% to 7%.

In another example, the discontinuities which form in thecircumferential elements and/or rings will typically comprise partial ortotal breaks, separations, gaps in the structure of the circumferentialscaffold which reduce or eliminate the stress areas, stiffness, hoop,circumferential, and/or radial strength of the scaffold (or ringcomponent of the scaffold as described more particularly below and/or inthis application) and/or in the separation region. Most commonly, thediscontinuities will be total breaks which allow two resulting free endsin the scaffold or ring or circumferential element to move apart fromeach other in response to remodeling or other expansion of the bodylumen and/or the stent. In one example the discontinuities where the twofree ends are contained by a material comprising a sleeve or a coatingwherein the sleeve or coating material can be non-degradable ordegradable such as a polymer, wherein the sleeve or coating stretcheswhen the free ends move apart. In another example the discontinuitiesare contained by means of the discontinuity geometry (such as certainkey and lock designs and other type of geometry) to hold the structuralelement containing discontinuities together upon deployment from acrimped configuration to an expanded configuration, wherein thediscontinuity is formed before patterning, during patterning, or afterpatterning, and is held together by the design configuration of theseparation region forming said discontinuities as described above and/orin the entire application. The discontinuity in this case allows forcrimping and/or deployment of the stent while maintaining the free endsof the structural elements containing said discontinuities to be heldtogether and providing for sufficient strength after deployment of thestent to support a body lumen. The discontinuities in this case canallow movement of the free ends of the structural element in one or moredirections after deployment, preferably in the radial direction onlyafter deployment, more preferably substantially only in the radialdirection, most preferably said movement primarily in the radialdirection, or said movement is in a radial and/or circumferentialdirection. In one example, At least some of the rings or other portionsof the scaffold will have at least one such discontinuity, but moretypically each ring will have at least one discontinuity and some or allof the rings may have two or more discontinuities. Individual scaffoldrings may have the same number or different numbers of discontinuities,and not all scaffold rings need have discontinuities. For example, ringsat or near an end of the scaffold may be free from discontinuities, e.g.to limit the wishbone effect. In a further example at least some ringswill have a number of discontinuities ranging from 1 to the same numberof crowns, preferably a number of discontinuities ranging from 1 to ¾ ofthe number of crowns on said ring, and/or will have a number ofdiscontinuities ranging from 1 to same number of the struts on saidrings, preferably a number of discontinuities ranging from 1 to ¾ of thenumber of struts on said ring, and/or will have a number ofdiscontinuities ranging from 1 to ½ of the number of crowns on saidring, and/or will have a number of discontinuities ranging from 1 to ½of the number of struts on said ring, and/or will have a number ofdiscontinuities ranging from 1 to ¼ of the number of crowns on saidring, and/or will have a number of discontinuities ranging from 1 to ¼of the number of struts on said ring, and/or will have a number ofdiscontinuities ranging from 1 to 10 on said ring, preferably a numberof discontinuities ranging from 1 to 5 on said ring, more preferably anumber of discontinuities ranging from 1 to 4 on said ring, and/or anumber ranging from 1 to 3 on said ring, and/or a number ranging from 1to 2 on said ring.

In one example, the physiologic environment causes such discontinuitiesto form (in other examples the discontinuities are formed independent ofthe physiologic environment) may be characterized by any physicalcondition associated with the body lumen into which the prosthesis is tobe implanted. For example, the physiological environment or conditionmay comprise any one or more of the following: a physiologictemperature, e.g. 37° C., as maintained in the body lumen, or in a waterbath heated to about 37° C., and/or a physiologic pressure, and/or,pressure and/or pulsating pressure, and/or introduction of a drug agentsuch as vaso-dilator or vaso-constrictor, as described in thisapplication. Additionally, the physiologic environment may compriseblood or other aqueous media into which the scaffold has been implanted,particularly oxygenated blood that may enhance corrosion of certainfeature. Often, the physiologic environments will comprise pulsation ofa blood vessel, particularly an artery, which can subject the implantedscaffold to mechanical stress which in turn can fatigue and breakparticular features formed in the scaffold structure. Thediscontinuities, whether resulting from degradation, corrosion,dissolution, or mechanical stress, will in one example typically formfrom thirty days to six months, but can also form from few days to 1year after initial expansion of the circumferential scaffold andexposure of the expanded scaffold to the environment of the body lumen.In other embodiments, discontinuities form in a water bath at ambienttemperature.

In one example, the separation regions may comprise any one of a varietyof structures in or modifications of the scaffold, for example includingnotches, variations in the grain structure, pre-formed breaks which arerejoined by degradable polymers, adhesives, sleeves, rivets, or thelike.

In one particular example of the separation regions comprises a key andkey hole, and/or a key and lock, and/or ball and socket, and/or hookjunction which is immobilized and/or held together as formed, and/orafter forming, and/or before deployment, and/or before expansion, and/orduring deployment, and/or during expansion, and configured to separateand/or form a discontinuity, after deployment, and/or after additionalexpansion in the physiologic environment. For example, the key and keyhole, and/or key and lock, and/or ball and socket, and/or hook junctionsmay be initially held together by means, such as by a material such as apolymer, cement, adhesive, solder, and/or the like, which degrades inthe physiologic environment, where the key and key hole, and/or key andlock, and/or ball and socket, and/or hook are configured to separate orform a gap once the means holding the junctions comes apart or degrades,or once the key and key hole, and/or key and lock, and/or hook junctionis free from the material such as polymer, cement, adhesives, solder,e.g., in response to normal pulsations of the blood vessel or other bodylumen, or other physiologic conditions described throughout thisapplication. In one example, the key and key hole, and/or key and lock,and/or ball and socket, and/or hook junctions may be substantially heldtogether by the geometry of the junction which restricts orsubstantially restrict movement of the junction in one or moredirections sufficiently to allow for stent deployment and for the stentto have a strength sufficient to support a body lumen after deployment(initial deployment). In a preferred example such junction remainssubstantially held together upon deployment (expansion from crimpedconfiguration to an expanded larger configuration) and wherein the stenthas sufficient strength in the expanded configuration to support a bodylumen. In this preferred example, the junction means to hold it togetheris the geometry of the junction such as the type of key and key hole,and/or key and lock, and/or ball and socket, and/or hook, and/or othertype of junction. The separation region junction can also be a buttjunction connecting and/or joining two ends of a stent structuralelement and/or a ring, said ends having various shapes and/or crosssectional shapes (including substantial shapes type) such as round,and/or ball, and or square, and/or rectangle, and/or a nerve synapsetype junction, and/or other type shapes, and/or substantially suchshape. In one example the deployment means such as balloon catheterprovides for holding the discontinuities together upon deployment of thestent and wherein the stent is allowed to have controlled movement afterdeployment in one or more directions, preferably in the radialdirection, after deployment, and wherein the stent has sufficientstrength after deployment from a crimped configuration to an expandedlarger configuration.

The separation regions in another example may also comprise a simplebutt joint or overlapping sections of stent structural elements wherethe structural elements are solid wire (having various shapes such assubstantially round, rectangle, and/or square, and/or nerve synapse,and/or other shapes), and/or hollow wire/tube structural elements(hollow at least in regions adjacent to the separation regions) havingopposed free ends which are temporarily joined by means, such as anadhesive and/or connector and/or polymer and/or solder and/or sleevewhich degrades and/or separate and/or discontinue in the physiologicenvironment. Such means can hold the free ends together by placing thembetween the free ends, adjacent to the free ends, covering the freeends, inside the hollow section of the free ends, and/or combination ofall the above, of said structural elements.

In still other instances or examples, the separation regions maycomprise notches or thinned sections formed in the circumferential ringsand/or circumferential structural elements, where these notches orthinned sections will preferentially erode or fatigue in the physiologicenvironment, forming partial or complete separations which allowexpansion of the circumferential rings thereafter. In still otherembodiments or examples, the separation regions may comprisemodifications to the material of the circumferential ring itself. Forexample, in metallic rings, the separation regions may have modifiedgrain boundaries which are selected to preferentially break and/or erode(including corrode) in the physiologic environment when compared to theremaining regions of the circumferential ring. Other examples are jointsmay be formed beginning with an intact circumferential ring, forming oneof more breaks in the ring, and thereafter rejoining the breaks withmeans such as sleeve, adhesives, solder, connectors, coating, and/or thelike, which are configured to degrade or erode or fatigue or break orseparate in the physiologic environment. For example, solder, adhesivesand/or polymer may be applied to the butt and/or or overlapping and/orhollow ends of the resulting joint. Alternatively, connectors maycomprise sleeves, rings, coils, or other circumscribing structure whichholds the joint together until such structures degrade and/or separatein the physiologic environment. In a preferred example a sleeve orcoating comprising a polymer such as parylene can be applied whichallows the separate free ends of the joint and/or junction to becontained within such sleeve or coating.

In another example the stent comprising a non-degradable metal or metalalloy, said stent comprising a structure comprising a plurality of ringswhere the rings comprising struts joined by crowns where at least someof the rings have at least one crown and no more than ¾ of the number ofcrowns (preferably at least one and no more than ½ the number of crowns)are formed and/or patterned to have said crowns cross sectional areabeing smaller and/or smallest than the cross sectional area of anadjacent crown and/or the largest crown cross sectional area within saidring. Cross sectional area can be measured at approximately the peak ofthe crown and/or at any other point/section on the crown. The crosssectional area of the smaller (including smallest) crowns ranges from25% to 90% smaller than an adjacent crown cross sectional area and/orthe largest crown cross sectional area within said ring, (preferably 50%to 75% smaller). The cross sectional area of the smaller (includingsmallest) crowns ranges from 400 micron squared to 3000 micron squared,preferably ranges from 400 micron squared to 2500 micron squared, andmore preferably ranges from 400 micron squared to 1500 micron squared,such smaller cross sectional area crowns allowing said crowns to open upfurther after expansion. The smaller (including smallest) crowns canoptionally have a sleeve, and/or coating, and/or solder comprised frompolymer and/or adhesive and/or other material to hold the crown (and/orstruts joined by said crown) in a crimped or substantially crimpedconfiguration upon deployment of the stent, and where the sleeve and/orcoating and/or solder degrade and/or dissolve and/or loosen afterdeployment (expansion) allowing the stent to further expand as thesmaller cross sectional crowns are allowed to open and/or expand underphysiologic conditions. The stent has sufficient strength upondeployment to support a body lumen. In another example the stent hassufficient strength to support a body lumen upon deployment where thestent strength decreases after the sleeve, and/or coating, and/oradhesive, and/or solder, dissolves and/or degrades under physiologicconditions after deployment. The cross sectional area of at least ¼ to ¾of the crowns, preferably at least ½ to ¾ of the crowns, more preferablyat least ¾ of the crowns, ranges from 3500 micron squared to 25000micron squared, preferably ranges from 4000 micron squared to 10,000micron squared, and more preferably ranges from 4500 micron squares to8000 microns squared. The cross sectional area measurements in the aboveexample are of same type (or same) non-degradable material (metal ormetal alloy material) of the stent or structural element such as thecrown and does not include other materials such as polymers, metals,coatings, etc. that are on or within the crown, when comparing smallercross sectional area crowns to larger cross sectional area crowns.Alternatively, smaller cross sectional area crowns can be accomplishedby incorporating a different material from the non-degradable metal ormetal alloy in the crown region, or having less dense or weakermaterial, and/or having one or more of a groove, a hole, a dent, acrescent shape, a crown shaped, and/or a channel, in, on, and/or throughthe crown region. The groove, the hole, the dent, the crescent shape,the crown shaped, and/or the channel in, on, and/or through the crownregion can be filled and/or coated with at least one material comprisinga polymer, metal or metal alloy (preferably different from metal ormetal alloy forming the stent), adhesive, and/or solder, and/or othersuitable material. In this example the smaller cross sectional area isaccomplished by having a softer or weaker or less dense material or gapin the crown region which effectively reduces the cross sectional areaof the non-degradable metal or metal alloy in the crown (even though thetotal cross sectional area of said crown maybe similar to other crowncross sectional areas) compared to cross sectional area of same typemetal or metal alloy in adjacent crown (or larger cross sectional areaof same type metal or metal alloy). The material preferably is differentfrom the crown material. The material can remain in the crown region,dissolve, and/or degrade/erode after deployment to allow the stent touncage and/or further expand under physiologic conditions. The stentupon deployment has sufficient strength to support a body lumen andwhere the stent strength does not decrease after deployment, ordecreases after deployment, preferably decreases within 30 days afterdeployment, more preferably decreases within 3 months after deployment,and/or within one year after deployment. The material has lowerstiffness than the crown material (preferably 2-10 times lowerstiffness), softer, stretchable, and/or lighter than the crown material.The said crowns can have in one example a sleeve and/or a coating and/oradhesive containing said crown region and/or struts joined by saidcrowns. In another example, the stent exhibit increase in radial strainafter expansion, and/or decrease in radial strength after saidexpansion. In another example, said increase of radial strain and/ordecrease in strength, begins one week after expansion of the stent to 9months after expansion of the stent, preferable begins one month afterexpansion to 6 months after expansion, more preferably begins 2 monthsafter expansion to 6 months after expansion. In another example at leastsome struts have thinned cross sectional areas as described in thisparagraph,

In another example, the stent formed from non-degradable metal or metalalloy is patterned to have one or more regions on at least some rings orother structure “hollowed out” to create void regions or “voids” withinthe crown, strut, or other structural component of the stent scaffoldwhere the metal has been removed, e.g. by patterning, cutting (such aslaser cutting), abrading, or the like. Optionally, the voids may beentirely or partially filled with a degradable or non-degradable fillingmaterial which contributes to the strength of the scaffold for at leasta time after implantation so that the scaffold has sufficient initialstrength to support a body lumen. The filling material may be more orless stiff than the metal or metal alloy material of the stent, or insome cases may have an equivalent stiffness. The void may be completelyfilled, partially filled, or in some cases over-filled so that thefiller material extends beyond the boundary of the stent scaffold priorto void formation.

Such filled-voids on crown regions for example will deform uponexpansion of the stent and allow the compliance and strength of thestent to vary over time. In many examples, the filled-voids on thecrowns will enhance strength of the scaffold at the time of expansionand implantation, but will also reduce compliance. By using a fillermaterial that degrades, softens, or otherwise loses strength whenexposed to a vascular or other physiologic environment, however, thecompliance of the scaffold will increase which in turn increases thecomposite or composite compliance of the stent and blood vessel or otherbody lumen. While the strength may concurrently decrease, such reductionin strength is usually acceptable after the vessel or other body lumenhas been opened and the luminal wall at least partially healed. In thisway, at least some rings of the stent to uncage, to further expand,and/or to exhibit vaso-reactivity. The thickness of the metal or metalalloy surrounding the hollowed-out or void region in the crown regions(side surface region, luminal surface region, or abluminal surfaceregion) ranges from 10 microns to 50 microns, preferable ranging from 20microns to 40 microns. The hollowed out crown region can have a varietyof ways to be hollowed out such as: two side surface regions of thecrown region remain intact and the region between the two side surfaceregions is hollowed out, one side region and a luminal surface regionremain intact while the other side region and abluminal surface regionis hollowed out, two side surface regions and a luminal surface regionremain intact while the abluminal surface region gets hollowed out, allsurface region (abluminal, luminal, 2 sides) remain intact but the innercore of the crown region is hollowed out, and/or one side region, theabluminal surface region, and luminal surface region remain intact whilethe core gets hollowed out from the other side surface region, or other;such that the crown region allows uncaging of the stent after expansion.The combined total cross section area of the non-degradable metal ormetal alloy for the said one or more crown regions at at least onesection of the crown region ranges from 200 micron squared to 4000micron squared, preferably ranges from 400 to 3000 micron squared, andmore preferably ranges from 500 to 2500 micron squared. In anotherexample, the hollowed-out region is filled with another material(degradable or non-degradable), wherein the material after expansionallows the crown region, the ring, and/or the stent to uncage, and/or tohave increase in radial strain, and/or to have increase in radial strainand decrease in radial strength. In another example, at least some ofthe struts along at least some rings are hollowed out as described inthis section.

Voids may also be formed in the struts, and other components of ascaffold ring or other scaffold structure. For example, channels, slots,and the like can be formed over some or all of a length of at least somerings, including struts, crowns, and any other structural components. Aswith other voids described previously, the channels, slots, and the likemay be partially or fully filled with a second degradable polymeric ormetallic material, referred to herein as a “reinforcement material,” toprovide sufficient combined material strength to enhance the radialstrength of the stent immediately following expansion, wherein thereinforcement material typically degrades after expansion andimplantation to enhance compliance while typically also reducing stentstrength. The base non-degradable material of the struts, and othercomponents of a scaffold ring or other scaffold structure will typicallyhave a cross-sectional area in a range from 1000 μm² to 4000 μm²,preferably from 1500 μm² to 3500 μm², where the degradable reinforcementmaterial covering all or portions of the non-degradable material adds anadditional 40 μm to 120 μm to a thickness and/or a width of the scaffoldbase material component, and wherein the combined base and coveringreinforcement materials have sufficient strength to support a body lumen(and prevent recoil in vascular lumens) upon expansion, and wherein thecompliance increases and strength in at least some rings decreasesfollowing expansion and implantation to uncage the stent. Channel depthsare typically from 40% to 90% of the non-degradable material thickness,preferably from 50% to 85%, and more preferably from 60% to 80%, and thewidths of the channels and slots are typically from 40% to 90% of thenon-degradable material width, preferably 50% to 85%, more preferably60%-80%. Channel and slot widths and thickness can vary along the lengthof the channels and slots on at least some rings Channels may bedisposed on abluminal surface regions, luminal surface regions, and/orboth abluminal and luminal surface regions. Slots will typicallypenetrate from an abluminal surface to a luminal surface.

One or more thinned regions may alternatively or also be formed be alongsome or all of the rings or other circumferential elements of anon-degradable scaffold in order to increase scaffold compliance andpromote uncaging of the scaffold after implantation. Such thinned outregions may be present in crown regions, strut regions, or on othercomponents of a ring or other structure that affects circumferentialcompliance. By “thinned out,” it is meant that a crown, strut, or otherscaffold component has baseline cross-sectional dimensions over amajority of a length of that component, and that the baselinecross-sectional dimensions are reduced in a region is referred to asbeing “thinned out.” Thinned-out regions can be located in adjacentcrowns, in alternating crowns, in every third crown, or in otherpatterns or configurations to achieve sufficient strength to support abody lumen upon deployment and to increase compliance after expansion.Such thinned out regions can have a smaller thickness and/or widthand/or cross section relative to the baseline dimensions sufficient topromote uncaging after implantation. Without any further modification,the thinned out regions will usually provide both lower scaffoldstrength and an increased compliance in at least the thinned out regionof the component. Optionally, the thinned out regions can be reinforcedwith a coating, lamination, or other coupling of a reinforcementmaterial to provide strength upon expansion while usually degradingafter expansion to increase compliance. Such bio-degradablereinforcement materials can be similar to the filler materials describedelsewhere herein, typically being degradable polymers but also beingdegradable metals. Suitable reinforcement materials will degrade over atime period after implantation in or expose to a vascular environmentranging from 30 days to 3 years, preferably from 3 months to 2 years,more preferably from 3 months to 1 year. The base non-degradablematerial (base stent), usually metal or metal alloy comprises one ormore rings (or circumferential structural elements), usually a pluralityof rings, each ring comprises struts and crowns along the length of saidring, and wherein the base stent in some examples does not havesufficient strength to support a body lumen (or to maintain a bodylumen) in the absence of a reinforcement material coupled to the basestent, said reinforcement material having sufficient weight andthickness (such as a polymer coating) to increase the strength of thebase strength to being sufficient to support a body lumen (or maintain abody lumen open).

For example, thinned-out cross-sectional regions along a length of acircumferential ring may be coated, laminated, or otherwise covered withsufficient reinforcement material to reinforce the stent scaffold uponexpansion where the stent strength decreases and compliance increases asthe material degrades after expansion and exposure to a vascular orother luminal environment. The scaffold may be formed from anon-degradable base material component having a cross-sectional area ina range from 1000 μm² to 4000 μm², preferably from 1500 μm² to 3500 μm²,wherein the degradable reinforcement material covering thenon-degradable material adds additional 40 μm to 120 μm to a thicknessand/or a width of the scaffold base material forming an underlyingcomponent, and wherein the combined base and covering materials havesufficient strength to support a body lumen upon expansion, and whereinthe compliance increases and strength in at least some rings decreasesfollowing expansion and implantation to uncage the stent.

In another example in any of the examples in this application, the stentprosthesis exhibits one or more of the following: uncages afterexpansion (which also includes one or more of the following): increasein radial strain (or compliance), increase in radial strain (orcompliance) and decrease in radial strength, exhibit vaso-reactivity orvas-dilatation of the stented segment, further expand to a second largerconfiguration, being able to expand and/or contract after deployment,change in the shape configuration from the deployed shape configuration,change in the displacement of the stent in at least one dimension, havea displacement after expansion in at least one direction larger.

Suitable stent material including polymeric, metallic (matel and metalalloys), adhesives, coatings, solder, sleeves, sealants, fixationmaterials, cement, energy fixation, include but are not limited to thefollowing: adhesives and fixation materials include but are not limitedto adhesives, sealants, and potting compounds such as cyanoacrylate suchas polyalkyl-2-cyanoacrylate, methyl-2-cyanoacrylate, ethyl-2-acrylate;n-butyl cyanoacrylate, 2-octyl cyanoacrylate, or others; epoxy;epoxamine; UV-curable from Loctite, Dymax, Master Bond, or other;acrylic; silicone; hot melt; polyurethane; gorilla glue; lysine basedadhesive such as TissueGlu, Sylys Surgical Sealant, or others; fibringlue; beeswax. Other fixation materials may also be used, such as solderor fusible alloy material such as tin or its alloy such as Sn97Cu3,Sn50Zn49Cu1, Sn95.5Cu4Ag0.5, Sn90Zn7Cu3, Sn98Ag2, Sn96.5Ag3Cu0.5,Sn91Zn9, Sn85Zn15, Sn70Zn30, Sn89Zn8Bi3, Sn83.6Zn7.6In8.8,Sn86.9In10Ag3.1, Sn95Ag3.5Zn1Cu0.5, Sn86.5Zn5.5In4.5Bi3.5, Sn95Sb5,Sn96.2Ag2.5Cu0.8Sb0.6, Sn90Au10, or others; Indium or its alloy such asIn97Ag3, In90Ag10, In50Sn50, In52Sn48, or others; zinc or its alloy suchas Zn95A15, Zn60Sn40, Zn95Sn5, or others; bismuth or its alloy such asB57Sn42Ag1, Bi58Sn52, or others; gold or its alloy such as Au80Sn20,Au98Si2, Au87.5Ge12.5, Au82In18, Other means for fixation includes laserbonding or welding or fusing, or other means of energy fixation(including bonding or joining), or solvent based, polymer dispersion orneat adhesives, sealants, and potting compounds such as cyanoacrylatesuch as polyalkyl-2-cyanoacrylate, methyl-2-cyanoacrylate,ethyl-2-acrylate; n-butyl cyanoacrylate, 2-octyl cyanoacrylate, orothers; epoxy; epoxamine; UV-curable from Loctite, Dymax, Master Bond,Henkel, or other; acrylic; silicone; hot melt; polyurethane; gorillaglue; polyester; polylactide and their copolymers and blends;polytrimethylene carbonate and their copolymers or blends; polyvinylalcohol; polyvinyl acetate; ethylene-vinyl acetate (a hot-melt glue);phenol formaldehyde resin; polyamide; polyester resins; polyethylene (ahot-melt glue); polypropylene; polystyrene; Polycarbonate;polychloroprene; natural rubber; silicone rubber; lysine based adhesivesuch as TissueGlu, Sylys Surgical Sealant, or others; fibrin glue;beeswax; bioadhesives such as casein, mussel adhesive proteins, andcollagen, combination thereof, or the like, solder or fusible alloymaterial such as tin or its alloy such as Sn97Cu3, Sn50Zn49Cu1,Sn95.5Cu4Ag0.5, Sn90Zn7Cu3, Sn98Ag2, Sn96.5Ag3Cu0.5, Sn91Zn9, Sn85Zn15,Sn70Zn30, Sn89Zn8Bi3, Sn83.6Zn7.6In8.8, Sn86.9In10Ag3.1,Sn95Ag3.5Zn1Cu0.5, Sn86.5Zn5.5In4.5Bi3.5, Sn95Sb5,Sn96.2Ag2.5Cu0.8Sb0.6, Sn90Au10, or others; Indium or its alloy such asIn97Ag3, In90Ag10, In50Sn50, In52Sn48, or others; zinc or its alloy suchas Zn95A15, Zn60Sn40, Zn95Sn5, or others; bismuth or its alloy such asB57Sn42Ag1, Bi58Sn52, or others; gold or its alloy such as Au80Sn20,Au98Si2, Au87.5Ge12.5, Au82In18, combination thereof, or the like.Suitable stent materials non-degradable in the vascular or otherphysiologic environment include but are not limited to metals and metalalloys, such as stainless steel, such as 304V, 304L, and 316LV stainlesssteel; steel alloys such as mild steel; cobalt-based-alloys such ascobalt chrome; L605, Elgiloy®, Phynox®; platinum-based alloys such asplatinum chromium, platinum iridium, and platinum rhodium; tin-basedalloys; rhodium; rhodium based-alloys; palladium; palladium base-alloys;aluminum-based alloys; titanium or their alloy; rhenium based-alloyssuch 50:50 rhenium molybdenum; molybdenum based-alloys; tantalum; goldand gold alloys; silver and silver alloys; shape memory metal or alloys;chromium-based alloys; nickel-titanium alloys such as linear-elasticand/or super-elastic nitinol; nickel alloys such asnickel-chromium-molybdenum alloys (e.g., INCONEL 625, Hastelloy C-22,Hatelloy C276, Monel 400, Nickelvac 400, and the like);nickel-cobalt-chromium-molybdenum alloys such as MP35-N;nickel-molybdenum alloys; platinum enriched stainless steel;combinations thereof; or the like, and other malleable metals of a typecommonly employed in stent and prosthesis manufacture. In otherexamples, the non-degradable material may comprise a non-degradablepolymer, such as polyaryletherketone; polyetheretherketone; polyimide,polyethylenes such as UHMW, HDPE, LDPE, or others; polypropylene;polyester; polyethylene terephthalate; polycarbonate; polysulfone;polyphenylsulfone; polyethersulpone, Ultem; polyetherimide;polyurethane; polyamide; nylon such as nylon 12, nylon 6, nylon 6-6, orothers; polyvinylchloride; PTFE; FEP; ETFE; PFA; PVDF;polyvinylchloride; acrylobutadiene styrene; Delrin;polymethylmethacrylate; polystyrene; polyacrylamide, polyphenylsufide;PEBAX; or other materials. In still other examples, the non-degradablematerial may comprise an elastic metal, such as a shape or heat memoryalloy, shape memory polymer, or superelastic materials, typically anickel-titanium alloy; a spring stainless steel; Ni50-Mn28-Ga22;copper-aluminium-nickel; alloys of zinc, copper, gold and iron;iron-based-alloys such as Fe—Mn—Si; copper-based-alloys such as Cu—Zn—Aland Cu—Al—Ni; poly(ε-caprolactone)dimethacrylate; PVDF/PMMA; PVDF/PVA;PLA/PVAc; or other, or the like. Examples of degradable material such asdegradable polymeric material comprise one or more of: lactides,caprolactones, trimethylene carbonate, glycolides, poly(L-lactide),poly-DL-Lactide, polylactide-co-glycolide (e.g.,poly(L-lactide-co-glycolide), copolymer ofpoly(L-lactide-co-epsilon-caprolactone (e.g., weight ratio of fromaround 50 to around 95% L-lactide to about 50 to about 5% caprolactone;poly (L-lactide-co-trimethylene carbonate), polytrimethylene carbonate,poly-caprolactone, poly(glycolide-trimethylene carbonate),poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids, polymers, blends, and/or co-polymers, orcombination thereof.

In another example, suitable materials including suitable stent materialincluding polymeric and metallic (degradable or non-degradable),adhesives, coatings, solder, sleeves, sealants, sealants, pottingcompounds, fixation materials, cement, energy fixation, elastomers andother type material, include but are not limited to: adhesives such ascyanoacrylate such as polyalkyl-2-cyanoacrylate, methyl-2-cyanoacrylate,ethyl-2-acrylate; n-butyl cyanoacrylate, 2-octyl cyanoacrylate, orothers; gorilla glue; lysine based adhesive such as TissueGlu, SylysSurgical Sealant, or others; fibrin glue; beeswax. Non-degradableadhesives, sealants, and potting compounds such as epoxy; epoxamine;UV-curable from Loctite, Dymax, Master Bond, or other; acrylic;silicone; hot melt; polyurethane; Degradable sleeve materials, stentmaterial, and coatings such as polyester; polylactide and theircopolymers and blends; copolymers of lactide, caprolactone, trimethylenecarbonate, glycolide; poly(L-lactide), poly-DL-Lactide,polylactide-co-glycolide (e.g., poly(L-lactide-co-glycolide); copolymerof poly(L-lactide-co-epsilon-caprolactone (e.g., weight ratio of fromaround 50 to around 95% L-lactide to about 50 to about 5% caprolactone;poly (L-lactide-co-trimethylene carbonate; polytrimethylene carbonate;poly-caprolactone; poly(glycolide-trimethylene carbonate);poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids; protein such as elastin, fibrin, collagen,glycoproteins, gelatin, or pectin; poly-serine; polycaprolactam;cyclodextrins; polysaccharides such as chitosan, and hyaluronan;alginate; polyketals; fatty acid-based polyanhydrides, amino acid-basedpolyanhydrides; poly(ester anhydride); polymer blends; and/orco-polymers; or combination thereof; or the like. Corrodible solder orfusible alloy such as Sn97Cu3, Sn50Zn49Cu1, Sn95.5Cu4Ag0.5, Sn90Zn7Cu3,Sn98Ag2, Sn96.5Ag3Cu0.5, Sn91Zn9, Sn85Zn15, Sn70Zn30, Sn89Zn8Bi3,Sn83.6Zn7.6In8.8, Sn86.9In10Ag3.1, Sn95Ag3.5Zn1Cu0.5,Sn86.5Zn5.5In4.5Bi3.5, Sn95Sb5, Sn96.2Ag2.5Cu0.8Sb0.6, Sn90Au10, orothers; Indium or its alloy such as In97Ag3, In90Ag10, In50Sn50,In52Sn48, or others; zinc or its alloy such as Zn95A15, Zn60Sn40,Zn95Sn5, or others; bismuth or its alloy such as Bi57Sn42Ag1, Bi58Sn52,or others. Non-corrodible solder or fusible alloy such as gold or itsalloy such as Au80Sn20, Au98Si2, Au87.5Ge12.5, Au82In18. Degradable andnon-degradable polymers include: polyester; polylactide and theircopolymers and blends; copolymers of lactide, caprolactone, trimethylenecarbonate, glycolide; poly(L-lactide), poly-DL-Lactide,polylactide-co-glycolide (e.g., poly(L-lactide-co-glycolide); copolymerof poly(L-lactide-co-epsilon-caprolactone (e.g., weight ratio of fromaround 50 to around 95% L-lactide to about 50 to about 5% caprolactone;poly (L-lactide-co-trimethylene carbonate; polytrimethylene carbonate;poly-caprolactone; poly(glycolide-trimethylene carbonate);poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids; protein such as elastin, fibrin, collagen,glycoproteins, gelatin, or pectin; poly-serine; polycaprolactam;cyclodextrins; polysaccharides such as chitosan, and hyaluronan;alginate; polyketals; fatty acid-based polyanhydrides, amino acid-basedpolyanhydrides; poly(ester anhydride); polymer blends; and/orco-polymers; or combination thereof; or the like. polyvinyl alcohol;polyvinyl acetate; ethylene-vinyl acetate (a hot-melt glue); phenolformaldehyde resin; polyamide such as nylon 12, nylon 6, nylon 6-6, orothers; polyester resins; polyethylene (a hot-melt glue), UHMW, HDPE,LDPE, or others; polychloroprene; polyaryletherketone;polyetheretherketone; polypropylene; polystyrene; polyester;polyethylene terephthalate; polycarbonate; polysulfone;polyphenylsulfone; polyethersulpone, Ultem; polyetherimide;polyurethane; polyvinylchloride; PTFE; FEP; ETFE; PFA; PVDF;polyvinylchloride; acrylobutadiene styrene; polyacetal such as Delrin;polymethylmethacrylate; polystyrene; polyacrylamide, polyphenylsufide;PEBAX; and/or co-polymers, and/or combination thereof. Elasticnon-absorbable polymeric or elastomers such as silicone rubber; C-flex;poly(n-butylmethacrylate); poly(n-butylmethacrylate) blended withpoly(methamethacrylate), Poly(hexyl methacrylate), andpolyvinylpyrrolidone; Kraton; poly(styrene-ethylene/butylene-styrene)(SEBS); poly(styrene-ethylene/propylene-styrene) (SEPS), poly(acrylicacid-b-styrene-b-isobutylene-b-styrene-b-acrylic acid;poly(styrene-b-isobutylene-b-styrene); polybutadiene; PVDF-HFPpoly(vinylidene fluoride-hexafluorpropylene); polyvinylpyrrolidone;poly(ethylene-co-vinyl acetate); phosphorylcholine; PEBAX; polyurethaneelastomers; Tecoflex; Biomer; Pellethane; corethane; silicone rubber;rubbers; elastomers; blends; copolymers; combination thereof; or thelike. Non-corrodible elastic metal or metal alloys such as shape or heatmemory alloy, shape memory polymer, or superelastic materials, typicallya nickel-titanium alloy; a spring stainless steel; Ni50-Mn28-Ga22;copper-aluminium-nickel; alloys of zinc, copper, gold and iron;iron-based alloy such as Fe—Mn—Si; copper-based alloy such as Cu—Zn—Aland Cu—Al—Ni; or the like. Metals or metal alloys that have high initialstrength and weaken over time include Ti6A14V, Ti5Al2.5Sn, orTi-10V-Fe-3Al; stainless steel such as SAF2507; zinc alloys such asZn5al, Zn10Al, Zn18Al, Zn30Al, platinum metal and its alloys; tin alloyssuch as Sn3.9Ag0.6Cu, Sn-3.8Ag-0.7Cu, SnPb, or SnPbAt; aluminum alloyssuch as A11.7Fe, A10.7Cu, A1.5MgScZr, Al6Mg0.2Sc0.15Zr, 3004, 8090,7075, 6061, or 5056; zirconium alloy such as Zr55Al10Ni5Cu30; magnesiumalloy such as AZ31B or MG11li5Al1Zn0.034Sc (LAZ1151); iron alloy such asFe29.7Mn8.7Al1C, 30HGSA alloy steel, 4140, C45 steel, Fe36Ni, or lowcarbon steel; Nickel Alloys such as Ni21Cr17Mo or Haynes 230.Non-corrodible (non-degradable) metals or metal alloys such asconventional titanium alloys such as Ti6A14V, Ti5Al2.5Sn, orTi-10V-Fe-3Al; stainless steel such as SAF2507; platinum metal and itsalloys; aluminum alloys such as A11.7Fe, A10.7Cu, A1.5MgScZr,Al6Mg0.2Sc0.15Zr, 3004, 8090, 7075, 6061, or 5056; zirconium alloy suchas Zr55A110Ni5Cu30; 304V, 304L, and 316LV stainless steel; steel alloysuch as mild steel; cobalt based alloy such as cobalt chrome; L605,Elgiloy, Phynox; platinum based alloy such as platinum chromium,platinum iridium, and platinum rhodium; tin based alloys; rhodium;rhodium based alloy; palladium; palladium base alloy; aluminum basedalloy; titanium or their alloy; rhenium based alloy such 50:50 rheniummolybdenum; molybdenum based alloy; tantalum; gold or their alloy;silver or their alloy (degradable); shape memory metal or alloy;chromium based alloy; nickel-titanium alloy such as linear-elasticand/or super-elastic nitinol; nickel alloy such asnickel-chromium-molybdenum alloys (e.g., INCONEL 625, Hastelloy C-22,Hatelloy C276, Monel 400, Nickelvac 400, and the like);nickel-cobalt-chromium-molybdenum alloy such as MP35-N; Nickel Alloyssuch as Ni21Cr17Mo or Haynes 230; or other; nickel-molybdenum alloy;platinum enriched stainless steel; combination thereof; or the like.Corrodible metals or metal alloys (degradable) include nickel, cobalt,tungsten; tungsten alloys of rhenium, cobalt, iron, zirconium, zinc,titanium; magnesium, magnesium alloys, magnesium alloy AZ31, magnesiumalloy with less than 20% zinc or aluminum by weight, without or with oneor more impurities of less than 3% iron, silicone, manganese, cobalt,nickel, yttrium, scandium or other rare earth metal, AZ31B orMG11li5A11Zn0.034Sc (LAZ1151); zinc or its alloy such as zinc alloyssuch as Zn5al, Zn10Al, Zn18Al, Zn30Al; bismuth or its alloy; indium orits alloy, tin or its alloy such as tin-lead, Sn3.9Ag0.6Cu,Sn-3.8Ag-0.7Cu, SnPb, or SnPbAt; silver or its alloy such as silver-tinalloy; cobalt-iron alloy; iron or its alloys such as 80-55-06 grade castductile iron, other cast ductile irons, AISI 1010 steel, AISI 1015steel, AISI 1430 steel, AISI 8620 steel, AISI 5140 steel,Fe29.7Mn8.7Al1C, 30HGSA alloy steel, 4140, C45 steel, Fe36Ni, low carbonsteel or other steels; melt fusible alloys (such as 40% bismuth-60% tin,58% bismuth-42% tin, bismuth-tin-indium alloys; alloys comprising one ormore of bismuth, indium, cobalt, tungsten, bismuth, silver, copper,iron, zinc, magnesium, zirconium, molybdenum, indium, tin; or othermaterial; or the like.

In another example or aspect, the present invention providesnon-degradable prostheses having rings with energy-responsive separationregions. Such endoluminal prostheses comprise a scaffold havingcircumferential rings patterned from a non-degradable material, wherethe scaffold is configured to expand from a crimped configuration to anexpanded configuration. At least some of the circumferential rings willhave separation regions configured to form one or more discontinuitiesin said circumferential rings in response to energy applied to theseparation regions after deployment, and/or after implantation of saidprosthesis in a body lumen. Such discontinuities allow the scaffold touncage and/or further expand, e.g. beyond an initial expansion diameterafter recoil if any, typically achieved by balloon expansion,self-expansion, or the like.

The energy which promotes or causes the discontinuity may be energyassociated with the site of implantation or may be energy from anexternal source directed at the site of implantation. For example, theseparation regions may be configured to fatigue in response to,introduction of a drug agent, and/or pulsation of a blood vessel orother body lumen in which the endoluminal prosthesis has been implanted.Alternatively, the separation regions may be configured to respond toexternal energy which results in heat and/or mechanical motion, e.g.,vibration, of the separation region. In particular, suchmotion-responsive separation regions may comprise notches, thinnedregions, junction, butt joints, key and lock designs, or other localizedregions or foci which in one example preferentially fatigue and breakingresponse to the applied energy and/or pre-formed separation regionswhich discontinue in response to the applied energy. For example, theseparation regions may comprise “living hinges” which cycle open andclose in response to the pulsation or application of external energy andseparate or eventually fatigue and break. In still other examples, theseparation regions may comprise modified grain boundaries in metalrings, where the grain bodies are particularly susceptible tovibration-induced fatigue.

In other embodiments or examples, the separation regions may comprisepre-formed breaks or pre-formed separations regions in thecircumferential rings, where those breaks or discontinuities arereconnected with connectors configured to open in response to applied orendogenous energy (or in response to physiologic condition). Typicalforms of externally applied energy include ultrasound, drug agents,heat, magnetism, radio frequency energy, high intensity focusedultrasound (HIFU), and the like.

In other examples and/or embodiments, the separation regions maycomprise a key and lock junction formed in the circumferential ringsand/or circumferential structural elements, where the key and lockjunctions are initially immobilized before or during expansion or uponexpansion but configured to open in response to applied energy, orphysiologic condition, either external or endogenous. In still otherexamples or embodiments, the separation regions may comprise a rivet orother fastener joining breaks in the circumferential elements, where thefasteners are configured to open in response to applied energy, eitherexternal or endogenous, or in response to physiologic conditions.

In another example and/or fourth aspect, the present invention providesnon-degradable or slowly degradable prostheses having rings withconstrained hinges and methods for their use and fabrication. Anendoluminal prosthesis comprises a scaffold as having a circumferentialring pattern from a non-degradable material. The scaffold is configuredto deploy from a crimped configuration to an expanded configuration, andthe circumferential rings have hinges which open as the scaffold isbeing deployed and/or after deployment. At least some of the hinges onat least some of the rings are constricted from expansion duringdeployment and are configured to open in response to a physiologicenvironment or application of external energy after deployment.Particular physiologic environments and external energies which canrelease the hinges from constriction have been well described above orthroughout this application.

In one example, by initially constraining at least some of the hinges ofthe circumferential rings, the scaffold will be initially expanded to adiameter which is appropriate for the body lumen being treated and willpossess sufficient strength to maintain patency of that body lumen whilestill in its configuration with the constrained hinge(s). Afterdeployment and/or over time, however, the initially constrained hingeswill be released from constraint, which lowers the effectivecircumferential rigidity of the scaffold. That is, with the addition ofmore hinges or other expansion regions, the force required toincrementally open the scaffold, preferably beyond its initiallyexpanded configuration, will be lowered. In this way, the endoluminalprosthesis will have a reduced energy to cage or jail the treated bodylumen, thereby allowing the scaffold to enlarge and/or lumen to enlarge.

In another example or aspect, the present invention provides anon-degradable prosthesis having rings with joint or active joints andmethods for their fabrication and use. An endoluminal prosthesiscomprises a scaffold having circumferential rings patterned from anon-degradable material. This scaffold is configured to deploy from acrimped configuration to an expanded configuration, and thecircumferential rings include struts connected by joints which open asthe scaffold is being deployed, typically by balloon expansion. At leastsome of the joints will be pivoted to allow the scaffold in its expandedconfiguration to uncage and/or further expand. The pivots or “activejoints” may in some cases be asymmetric. That is, the joints will allowradial expansion of the circumferential rings, but will limit radialcontraction of the rings.

In different embodiments or examples, the shapes of the reinforcingelements or bridging element can be substantially round (solid roundwire or hollow round wire), rectangular, square, egg-shaped, or othershapes and geometries. The size of the reinforcing elements in someexamples may be substantially the same size/geometry as the hinges,expansion regions, and/or struts to which the reinforcing elements arecoupled, while in other examples the size/geometry of the reinforcingelements may be smaller or larger than the expansion regions. In oneexample, the ends of the reinforcing elements are atraumatic, and/orsmooth, and/or have bulbous shapes or rounded shapes, and/or have largercross sectional area to reduce trauma to the vessel. In one example asurface finish of the reinforcing elements is similar to that of apolished vascular metallic stents. In another example, the surfacefinish is textured.

In one example of degradable material, the polymeric body of thecircumferential scaffold is configured to substantially degrade underphysiologic conditions within a period from 1 month to 3 years,preferably from 3 months to 2 years, more preferably from 6 months to 1year, after deployment of the endoluninal prosthesis. In anotherexample, the reinforcement elements are encapsulated at least in part bya material, such as a thin polymer material. Examples include Paryleneand C-Flex material.

In another example, the separation regions of a non-degradable scaffoldare configured to separate in a period of up to 3 years afterdeployment, typically ranging from 1 day to 3 years, 1 month to 3 years,preferably from 3 months to 2 years, more preferably from 6 months to 1year. In one example the separation region separate about the same timeperiod, in another example the separation regions separate at differenttime periods.

In another example the endoluninal prosthesis further comprises at leastone coating, preferably a degradable coating, on at least one surface ofthe stent prosthesis (scaffold prosthesis). In another example the stentprosthesis further comprises at least one drug on at least one surfaceof the stent prosthesis. In another example the stent prosthesis furthercomprises at least one coating containing at least one drug, on at leastone surface of the stent prosthesis. In a preferred example, thepolymeric material or adhesive joining or containing or holding togetherthe separation regions are stretchable type polymers or adhesivematerials (degradable or non-degradable) to allow no movement to somemovement of the separation regions without prematurely forming thediscontinuities (before deployment, or after deployment). This alsoallows for consistent performance of the scaffold and improved storageconditions and shelf life of the stent and separation regions to allowfor extended shelf life under various typical environmental conditionsof heat, humidity, and time. The material can withstand temperatureranging from 5° Celsius to 50° Celsius, preferably from 10° Celsius to40° Celsius, and from 1 months to 3 years shelf life, preferably from 1month to two years, or from one month to 18 months. At relative humidityfrom 10% to 95%, preferably from 20% to 70% relative humidity. Examplesof material are described in this application.

In one example the endoluminal prosthesis further comprises radiopaquemarkers. In a more specific example the radiopaque markers comprisenon-degradable radiopaque marker. In a preferred example thenon-radiopaque radio markers comprises a metal or metal alloy.

In one example the reinforcing elements and/or the separation regionsand/or the environmentally responsive separation regions are formed fromnon-degradable materials such as non-degradable metals and/or polymersor other material. The reinforcing elements and/or the separationregions and/or environmentally responsive separation regions mayalternatively be formed in whole or in part from a degradable(corrodible) material, such as a degradable metal (such as magnesium andmagnesium alloys), or a degradable polymer (such as a lactide polymer,co-polymer, and blends thereof); or a combination thereof. In oneexample the reinforcing elements and/or separation regions and/orenvironmentally responsive separation regions are formed from acorrodible material which corrode after implantation to uncage the stentor other endoluminal prosthesis, preferably uncaging the stentprosthesis without formation of unwanted by products such ashydroxyapatite materials adjacent to the separation region.

In one example, the endoluminal prosthesis is a stent prosthesiscomprising a substantially tubular structure, the tubular structure ispatterned, the stent prosthesis comprises separation regions, and thestent prosthesis is crimped to a smaller diameter, and being deployedfrom the crimped configuration to a larger expanded configuration, wherethe stent in the expanded larger configuration has sufficient strengthto support a body lumen and/or does not fracture and/or has low recoil.The stent after deployment in this example is configured to do one ormore of the following: the stent and/or circumferential structuralelements and/or rings are configured to separate, expand, formdiscontinuities, and/or come apart at least in one section and/or regionor more after deployment and/or after implantation, and/or the stentundergoes modification comprises unlocking, degradation, or containmentby a sleeve or material that does not prevent the separation region fromuncaging, of the separation region or material adjacent to theseparation region after deployment or implantation causing at least onepart of the stent structures and/or to separate, expand, and/or comeapart, and/or the stent expands further after deployment, and/or thestent expands further after deployment and after modification, and/orthe stent expands further after deployment radially, and/or the stentexpands circumferentially after deployment, and/or the stent expandsfurther after deployment and after assisted modification from a source(chemical, energy), and/or the stent is configured to push the lumen toexpand for a period after deployment or implantation, and/or the stentis configured to allow the lumen or vessel to expand/enlarge, or acombination thereof. The stent comprises a non-degradable material, orcomprising two non-degradable materials, or comprising a degradablematerial, or comprising two degradable materials, or comprising twodegradable materials and one non-degradable material, or comprisingnon-degradable material and a corrodible material, or comprising adegradable material and a corrodible material, or comprising adegradable material, and a corrodible material, and a non-degradablematerial. The stent may further comprise at least one coating on atleast one surface of the stent prosthesis, said coating is degradableand/or non-degradable coating. The materials above exclude markermaterial(s) that can be degradable or non-degradable. The stent mayfurther comprise at least one drug on at least one surface of the stent.The stent can also comprise at least one coating on at least one surfaceof the stent prosthesis.

In one example, the stent prosthesis comprises a structure, preferablysubstantially tubular structure, more preferably substantially tubularpatterned structure having separation regions. The stent prosthesis istypically expandable from a crimped configuration to a deployed expandedlarger configuration. The stent structure comprises at least one main orprinciple material on at least one section of the stent, preferably theframe material is degradable material such as a polymer material, andthe stent structure further comprises at least one piece of a secondmaterial, preferably a stronger material than the frame material, morepreferably a metal material, more preferably a non-degradable metalmaterial, interfacing with or coupled to at least said section of theframe material, preferably said section is a crown section of the stentstructure. The stent is deployed to a larger expanded configuration. Thestent in the expanded deployed configuration has sufficient strength tosupport a body lumen, and/or expand without fracture, and/or expand withlow recoil. The stent undergoes modification after deployment where themodification comprises degradation of at least part of the framematerial, and/or degradation of at least part of the second material,and/or corrosion of at least first material, and/or corrosion of atleast part of the second material, or combination thereof. The stentafter modification comprises one or more discontinuity in at least onering, and/or at least one discontinuity in at least one crown, and/or atleast one discontinuity in at least one strut, and/or a combinationthereof. In another example the stent after modification has at leastone discontinuity in at least part of the frame material, and/or atleast one discontinuity in at least part of the second material, and/orat least one discontinuity in adjacent parts of the frame and secondmaterial. In another example, the stent after modification furtherexpands to a larger configuration from the configuration beforemodification, and/or further expands to a larger configuration from thedeployed configuration, and/or further expands to a larger configurationfrom a “recoil after deployment” configuration, and/or further expandsto a larger configuration for any of the previous causes in at least onering of the stent prosthesis, and/or further expands to a largerconfiguration in at least one ring other stent prosthesis wherein thering is located about the mid portion of the stent length. In anotherexample, the at least one discontinuity of at least one ring of saidstent after modification allows the stent to further expand at said atleast one ring under physiologic pressure. In another example, the stentprosthesis comes apart after deployment and/or modification in at leastone ring, crown, and/or strut. In one example the stent prosthesis afterdeployment and/or after modification and/or after coming apart has astructure, and/or has a tubular structure, and/or has a tubularpatterned structure, and/or has a substantially maintained tubularstructure, and/or has at least part of a structure, and/or has a atleast one window, and/or substantially has no structure, and/orcomprises at least one crown structure, and/or comprises at least onestrut, and/or comprises at least one link, and/or has a strength, and/ora combination thereof.

In a particular example, the stent comprises a substantially tubularpatterned structure comprising a plurality of rings, (serpentine,diamond, zig-zag, and/or other open cell or closed cell structure),wherein the ring comprises crowns and struts, wherein at least somerings are connected to adjacent rings by at least one link, or in somecases some adjacent rings are connected together in at least onelocation.

In an example a scaffold or ring material comprises metal and/or metalalloy. The metal and/or metal alloy may be non-degradable ordegradable/corrodible. The metal herein excludes markers and markermaterial which can be metal or metal alloy and can be degradable ornon-degradable. The corrodible metal or metal alloy corrodes in a periodranging from 1 month to 10 years, preferably in a period ranging from 3months to 5 years, and more preferably in a period ranging from 3 monthsto 3 years.

In an example the second material (or reinforcement elements) has atleast two ends, wherein the ends are deburred, shaped into a ball, ashape like a “nerve synapse,” and/or smoothed, to prevent injuring thelumen or vessel, and/or causing inflammation after the stent come apart,and/or after modification. In another example the stent is configured tonot break apart other than in the separating region and/or the sectionconfigured to break apart by reducing stress areas and/or fatigue areas,on the stent after modification, and/or after separation of theseparation region forming discontinuities and/or breaking apart of thestent.

In an example the main or frame material comprises a polymeric material.The polymeric material may be degradable or non-degradable. In oneexample the polymeric material degrades in a period ranging from 1 monthto 10 years, preferably ranging from 3 months to 5 years, morepreferably degrades in a period ranging from 3 months to 3 years.

In an example the main or frame material is non-degradable, and/ordegradable at a faster rate than the second material (reinforcementelements), and/or degradable at a substantially the same rate as thesecond material, and/or degradable at a slower rate than the secondmaterial.

In an example, the stent in any of the examples and/or embodiments inthis application is formed from one or more of the following: a tube, acontinuous wire or filament, a wire, a hollow wire hollow either hollowentirely or in certain regions such as less stress regions and/orsubstantially straight regions, or a braid, or mold, or by printing, orby extrusion, or by spraying, or by dipping, or by stamping, or acombination thereof. The stent has separation regions formed beforepatterning, during patterning, or after patterning, or after treatmentto form such separation regions and/or discontinuities. Means to holdsaid discontinuities are describes throughout this application.

In an example, a second reinforcing material coupled to or interfacingwith a structural scaffold material is embedded entirely inside theframe, or at least one surface or surface region is embedded inside atleast one surface or surface region of the frame, or at least twosurfaces embedded inside at least one surface of the frame, or at leastthree surfaces embedded inside at least one surface of the frame, or atleast one surface of the second material attached (and/or joined, and/orabut, and/or glued, and/or force fit) to at least one surface of theframe material. The at least one surface of the frame material may be anabluminal surface, may be the luminal surface, or may be a side surfaceof the frame material. The second material may be sandwiched within theframe material. In one example the second material has a discontinuity,where the second material discontinuity is held together or joinedtogether by said frame material, and/or glue, and/or a coating.

In an example, the second reinforcing material may in the form of one ormore pieces comprising one or more of a wire, ribbon, strut, crown,link, and/or filament. A cross-section of the piece(s) may have any oneof a variety of shapes comprising round or substantially round,rectangle or substantially rectangle, square or substantially square,oblong or substantially oblong, egg shaped or triangle, or other shapes.The length, number, and location of the pieces vary and maybe at leastone or more on at least one or more stent rings, ranging from the lengthof a stent strut or smaller, the length of a stent crown or smaller, thelength of a stent link or smaller, and/or the length of a stent ring orsmaller. Preferably, the pieces of the second material are on/in/aroundat least one stent crown in at least one stent ring, and/or on/in/aroundat least two stent crowns in at least one stent ring, and/oron/in/around substantially all stent crowns or part of a stent crown inat least one stent ring of the stent, and/or on/in/around all except oneof a stent crown on at least one stent ring, and/or on at least onering, on/or on at least one ring about the middle of the stent length,and/or on at least one window of the stent patterned structure, and/oron at least one strut or part of a strut, and/or on at least one link orpart of a link, and/or other variety or combination thereof. In oneexample a patterned stent structure comprises plurality of windows eachwindow comprises reinforcing material comprising at least two crown, andat least four struts. In another example the window comprises at leastfour crowns, and at least four struts, and at least one or at least twolinks. In another examples links maybe straight, and/or or have shapessuch as S-shaped link, V-shaped link, M-shaped link, and/or other linkshapes. In an example, at least one structural element (comprisingcrown, strut) in each window has a separation region configured toexpand and/or have a discontinuity and/or separate. In another example,the structural element comprises a plurality of circumferential ringscomprising one or more windows, wherein each window has at least oneseparation region configured to expand and/or have a discontinuityand/or separate.

In a preferred example it is desired to have a stent structure havingseparation regions, wherein the stent after deployment formsdiscontinuities in said separation regions (or such discontinuities areformed before deployment and held together by means of design geometryor deployment means such as balloon catheter), or other type ofembodiments of this application, wherein the stent structure issubstantially maintained after said separation regions come apart (orseparate), and/or move in one or more direction. The benefit of having astent structure, preferably along the length of the stent length or partof the stent length, helps prevent vulnerable material underneath thestent such as vulnerable plaque from rupturing into the blood vessel andcausing harm. The stent structure is sufficient to prevent (or hold) avulnerable material (such as vulnerable plaque) in a body lumen. Inanother example, the stent structure after deployment and/or aftercoming apart and/or after forming discontinuities is substantiallysufficient to support a body lumen. In another example, the stentstructure after deployment and/or after coming apart and/or afterforming discontinuities is substantially sufficient to support a bodytissue.

In one example the at least some structural elements of the stent uncageand/or come apart and/or have separation regions comprises one or moreof un-fix, un-hold, un-done, un-latched, un-attach, detached,disconnected, break up, break apart, push, push apart, separate, pullapart, create a gap, create a space, disintegrate, corrode, degrade,fragment, fracture, shatter, splinter, decompose, unlock, break down,deteriorate, degenerate, decay, discontinue, become free, and/orcombination thereof, of said stent or said stent structural element, asformed, after treatment (including modification), and/or afterdeployment, under physiologic conditions. Stent structural elements inone example comprises one or more of rings, crowns, struts, and/orlinks. Stent structural elements in another example comprises one ormore of rings, said rings comprise crowns, and/or struts.

In an example, the stent prosthesis is deployed to the expanded largerconfiguration under physiologic conditions and/or simulating conditionscomprising in air, and/or in air at ambient temperature, and/or in airat 37° C. temperature, and/or in water, and/or in water at ambienttemperature, and/or in water at 37° C., and/or in a body lumen, and/orat body temperature, and/or in a tube, under pressure, under pulsatingpressure, and/or combination thereof.

In an example, the stent prosthesis is deployed to the expanded largerconfiguration and undergoes modification in air, and/or in air atambient temperature, and/or in air at 37° C. temperature, and/or inwater, and/or in water at ambient temperature, and/or in water at 37°C., and/or in a body lumen, and/or at body temperature, and/or in atleast one solvent, and/or in at least one solvent or corrosion inducingagent at ambient temperature, and/or in solvent or corrosion inducingagent at 37° C., and/or in a tube, and/or pressurizing the stent at 1.5psi to 5 psi, under pressure, under pulsating pressure, and/oraccelerated fatigue, and/or accelerated any of the conditions, and/orcombination thereof.

In another example or aspect of this invention, a non-degradable stentprosthesis comprises a structure, wherein the structure comprising awire, hollow wire (hollow at least in some regions where it is hollow asformed and/or after treatment (modification)) where the wire and/orhollow wire are patterned into a stent, preferably a substantiallytubular stent structure, more preferably a substantially tubularpatterned stent structure wherein the stent is patterned from a tube.The stent prosthesis is expandable from a crimped configuration to adeployed larger or expanded configuration. The stent structure comprisesa strong material, such as a non-degradable polymeric or metal(including metal alloy) such as metal stainless steel or cobalt chrome.The material is configured to have a at least one section and/or regionin at least one ring where the material will come apart (environmentallyresponsive separation region, or separation regions) after deployment,and/or after modification; and/or the material is configured to have atleast one discontinuity in at least one ring, and/or at least onediscontinuity in at least one strut, and/or at least one discontinuityin at least one crown, and/or combination thereof. The discontinuity inthe material is held together and does not substantially affect thecrimping and/or deployment of the stent to the larger expandedconfiguration, and/or the stent prosthesis has sufficient strength inthe deployed configuration to support a body lumen; and/or the materialis configured to have at least one discontinuity in at least one ring,and/or at least one discontinuity in at least one strut, and/or at leastone discontinuity in at least one crown, and/or combination thereof. Thediscontinuity in the material is held together and does notsubstantially affect the crimping and/or deployment of the stent to thelarger expanded configuration, and/or the stent prosthesis hassufficient strength in the deployed configuration to support a bodylumen. The material being held together comprises holding, latching,attaching, connecting, pushing together, pulling together, removing agap, removing a space, and/or locking, together the materialdiscontinuity adjacent parts. The means to hold the materialdiscontinuity parts together comprises a sleeve, an adhesive, a pressfit, a lock, a coating such as polymer or metallic coating, a gel,solder, and/or designs such as key and lock design. The stent in theexpanded deployed configuration has sufficient strength to support abody lumen, and/or expand without fracture, and/or expand with lowrecoil. The stent in one example undergoes modification after deploymentwhere the modification comprises uncaging, un-fixing, un-holding,un-done, un-latching un-attaching, detaching, disconnecting, breakingup, breaking apart, pushing, pushing apart, separating, pulling apart,creating a gap, creating a space, disintegrating, corroding, degrading,fragmenting, fracturing, shattering, splintering, decomposing, unlock,break down, deteriorate, degenerate, decay, and/or discontinue, of atleast part of the material and/or the means holding the materialdiscontinuity parts together. The stent after modification comprises oneor more come apart material sections and/or discontinuity in at leastone ring, and/or at least one or more come apart material sectionsand/or discontinuity in at least one crown, and/or at least one or morecome apart material sections and/or discontinuity in at least one strut,and/or a combination thereof. In another example, the stent aftermodification allows the lumen or vessel to further enlarge from afterimplantation, and/or allows the stent to further expands to a largerconfiguration from the configuration before modification, and/or furtherexpands to a larger configuration from the deployed configuration,and/or further expands to a larger configuration from a “recoil afterdeployment” configuration, and/or uncage, and/or further expands to alarger configuration for any of the previous causes in at least one ringof the stent prosthesis, and/or further expands to a largerconfiguration in at least one ring of the stent prosthesis wherein thering is located about the mid portion of the stent length. In anotherexample, the at least one or more come apart material sections(separation regions) and/or discontinuity of at least one ring of saidstent after modification allows the stent to uncage and/or furtherexpand at said at least one ring under physiologic pressure. In anotherexample, the stent prosthesis comes apart after deployment and/ormodification in at least one ring, crown, and/or strut. In one examplethe stent prosthesis after deployment and/or after modification and/orafter coming apart and/or after the material discontinue has astructure, and/or has a tubular structure, and/or has a tubularpatterned structure, and/or has a substantially maintained tubularstructure, and/or has at least part of a structure, and/or has a atleast one window, and/or substantially has no structure, and/orcomprises at least one crown structure, and/or comprises at least onestrut, and/or comprises at least one link, and/or has a strength, and/ora combination thereof.

In one example the means to hold the material together and/or to holdthe material separation regions and/or discontinuity together, and/or toprevent the stent from coming apart before deployment, compriseadhesive, metal, polymer, coating, solder, press fit, welding, weavingor braiding a material, and/or other. In one example said meansdecomposes, degrades, corrodes, come unlocked, and/or unfit in a periodranging from 1 months to 5 years, preferably from 3 months to 3 years,more preferably from 3 months to one year. In one example the stentmaterial degrades after said means degrades and/or corrodes and/orunlocks, etc.

In another preferred example a stent prosthesis comprising a structure,where in the structure separation regions and/or discontinuity islocated in areas not affecting radial expansion, and/or orcircumferential expansion, preferably in lower stress areas such asstruts, or strut regions.

In another example a stent prosthesis is configured to have a patternedstructure where the structure has separation regions discontinuity suchas a key and lock, an abut, two plates, press fit, ratchets, rivets,inserts, magnets, or other, on at least one strut, and/or on at leastone crown, such that the stent after deployment, and/or after deploymentand after modification, allows the lumen or vessel to further enlarge,and/or uncage, and/or separate.

In another example a stent prosthesis is configured to have a patternedstructure where the structure comprises a plurality of rings wherein therings in one example is serpentine rings, wherein the rings comprisescrowns and struts, wherein at least one crown and two struts are held inthe crimped configuration by a coating and/or a sleeve, wherein thestent after deployment and modification comprising degradation of saidsleeve and/or coating allows the stent to uncage and/or further expandto a larger configuration, and/or allow the lumen or vessel to enlarge.

In another example a stent prosthesis is configured to have a patternedstructure where the structure comprises a plurality of rings wherein therings in one example is serpentine rings, wherein the rings comprisescrowns and struts, wherein at least one crown and/or at least one strut,on at least one ring are configured to have separation regions and/orcome apart at at least in one section or region after deployment andunder physiologic condition such as after fatiguing of said section orregion. Said stent structure after coming apart allows the stent touncage, and/or further expand to a larger configuration, and/or allowthe lumen or vessel to enlarge.

In another example a stent prosthesis is configured to have a patternedstructure where the structure comprises a plurality of rings wherein therings in one example is serpentine rings, wherein the rings comprisescrowns and struts, wherein at least one crown and/or at least one strut,on at least one ring are configured to come apart at at least onesection or region after deployment and under physiologic conditions suchas after fatiguing of said section or region. Said stent structuresafter coming apart allows the stent to uncage, and/or further expand toa larger configuration, and/or allow the lumen or vessel to enlarge.

In another example, a stent as in any of the examples above isconfigured to further expand after implantation using an external energysource wherein the energy source comprises magnetic field, infraredheat, inducing heat, ultrasound, and the like.

In another example in any of the examples above wherein the stentmaterial comprising the stent structure is a shape memory materialwherein the stent can uncage, and/or further expand after deploymentusing a shape memory material such as nickel-titanium alloy (NiTiavailable under the tradename Nitinol®), and where in the shape memorymaterial expands the stent further after deployment to a largerconfiguration, wherein the stent undergoes modification such as havingseparation regions wherein the stent comes apart or formsdiscontinuities in at least one section or region of the stent, and/orcomes apart in at least one ring, wherein the stent structure(s) aftercoming apart slows the further stent expansion, and/or stops the stentfurther expansion, and/or stops causing injury or inflammation to thevessel wall.

In another example in any of the examples above wherein the stentmaterial comprises a material that additionally softens aftermodification or after expansion under physiologic condition, such asPlatinum alloys, wherein the softening of said material reduces thestresses after deployment on the vessel wall and potentially brings thecompliance of the vessel and stent closer from before softening of thematerial.

In a preferred example, the pieces, and/or structure of stent, and/orstructure or part of a structure after modification and after the stentcomes apart is configured to have a shape and/or structure to avoiddislodging such pieces or structure elements into the blood stream.Examples include 2-D, and/or 3-D structures, stent windows, structurescomprising part of stent windows, structures comprising at least onecrown shape, structure comprising at least one crown and at least onelink shapes, structure comprising at least one crown, at least twostruts, and at least one link shapes, a structure comprising at leastone crown and at least two struts shapes.

In another example, the stent prosthesis is capable of being deployedfrom the crimped configuration to the larger expanded configurationunder one or more of the deployment condition in a previous example.

In another example the stent can be deployed at a rate of 1-2 atm perseconds, the stent is capable of being deployed beyond the labeled(nominal/intended deployed) diameter without fracture.

In preferred example of corrodible material such as magnesium, the stentis configured to have sections or regions wherein the material does notdegrade (corrode), and wherein said section or region would not degrade,providing stent sections or regions that do not cage the lumen or vesselproviding for a lumen or vessel capable of enlarging as a result of nothaving by product from the magnesium stent in said sections that wouldresult in caging the stent due to the hydroxyapatite by product cagingthe vessel.

In one example the stent comprising the separation regions or sectionscoming apart, and/or degrading, and/or corroding, and/or the stentsection discontinue, and/or unlock, after deployment in a period from 1day to 3 years, 1 month after deployment to 3 years, preferably from aperiod ranging from 3 months to one year.

In another example, the number sections or regions per at least one ringor in at least some rings that come apart, and/or unlock, and/ordegrade, and/or corrode for at least one ring ranges from 1 to 4,preferably ranges from 1 to 3, more preferably ranges from 1 to 2,wherein the stent has a structure after coming apart, and/or wherein thestent has no structure after coming apart, and/or wherein the stent inthe absence of tissue has an unsupported structure, or collapses, and/orwherein stent in the absence of tissue recoils, and/or wherein the stentin the absence of tissue recoils, or shrinks.

In another example, the number of sections per at least one ring thatcome apart, and/or unlock, and/or degrade, and/or corrode for at leastone ring ranges from 1 to 4, preferably ranges from 1 to 3, morepreferably ranges from 1 to 2, wherein the stent has a structure aftercoming apart, said structure has sufficient strength to support a bodylumen, or has no strength, and/or wherein the stent has no structureafter coming apart, and/or wherein the stent in the absence of tissuehas unsupported structure, or collapses, and/or wherein stent in theabsence of tissue recoils, and/or wherein the stent in the absence oftissue shrinks.

In another example, the number of sections per at least one ring thatcome apart, and/or unlock, and/or degrade, and/or corrode for at leastone ring ranges from 1 to 4, preferably ranges from 1 to 3, morepreferably ranges from 1 to 2, wherein the stent has a structure aftercoming apart, said structure has sufficient strength to support a bodylumen, or has no strength, and/or wherein the stent has no structureafter coming apart, and/or wherein the stent in the absence of tissuehas unsupported structure, collapses, and/or wherein stent in theabsence of tissue recoils, and/or wherein the stent in the absence oftissue shrinks.

In any one of the previous examples, the lumen or vessel is uncaged,and/or allowed to further enlarge or expand when the stent prosthesiscomprising reinforcing elements and/or comprising non-degradablematerial for stent strength, and/or when the remaining stent prosthesisnon-degradable material weight is lighter than the weight of the stentprosthesis comprising non-degradable and degradable material. In apreferred example, the stent prosthesis weight after degradation (orremoval) of degradable material (if any) ranging from 0.1 mg/mm to 1.5mg/mm, preferably ranging from 0.1 mg/mm to 1.2 mg/mm, and morepreferably ranging from 0.2 mg/mm to 0.9 mg/mm, and most preferablyranging from 0.2 mg/mm to 0.6 mg/mm. These weights exclude the weight ofnon-degradable radiopaque markers.

In another example, the conformability of the stent prosthesis (3-pointbend test) after formation of discontinuities, or after degradation ofdegradable material (if any) forming discontinuities is desirable to beas conformable as possible to avoid potential irritation andinflammation to the vessel wall after implantation. For example, theconformability of the stent prosthesis after formation ofdiscontinuities, or after removal (or degradation of degradablematerial) is preferably ranging from 0 N/mm to 0.05 N/mm, preferablyranging from 0 N/mm to 0.03 N/mm, more preferably ranging from 0 N/mm to0.1 N/mm In another example the conformability of the stent afterformation of discontinuities in the deployed configuration is improved(compared to before formation or compared to upon deployment of thestent) by at least 10%, or improved by at least 25%, or improved by atleast 50%, or improved by at least 75%. In another example theconformability after formation of discontinuities is improved (comparedto before formation or compared to upon deployment of the stent) by arange from 10% to 100%, preferably from 20% to 75%. In another examplethe radial strain of the stent after formation of discontinuities orafter deployment ranges from 2% to 5% in a simulated bench test (asdescribe but not limited to example 5). In another example, the radialstrain (or compliance) for the stent after formation of discontinuitiesand/or after deployment is larger than stent not having discontinuitiesby a factor ranging from 2 times to 10 times, preferably ranging from 2times to 5 times (as described but not limited to example 5).

In another example the stent or other endoluminal prosthesis is in anuncaged configuration prior to being deployed from a crimpedconfiguration, wherein the stent or other endoluminal prosthesis hasstrength in the deployed configuration to support a body lumen. Inanother example, the stent or other endoluminal is in an uncagedconfiguration in a circumferential direction prior to implantation ordeployment.

In another example, the stent or other endoluminal prosthesis isconfigured to uncage after deployment or after implantation, in aphysiologic environment, preferably configured to uncage in acircumferential fashion or direction by having at least one or more gaps(discontinuities) along the path of at least some, preferably every ringin the circumferential direction. Optionally, the stent can also unzipalong the longitudinal axes of the stent in one or more paths (or lines)through the formed discontinuities in a variety of patterns separatingthe stent into one or more segments. In one example, the stent does notunzip along the longitudinal axis, or unzips at least part of thelongitudinal axis of the stent.

In another example, uncaging of the stent or other endoluminalprosthesis comprises one or more of separation of the stent in at leastone region or section in at least one ring, at least one discontinuity,at least one break, at least one gap, ability of the stent to furtherexpand after deployment, ability of the lumen or vessel to positivelyremodel in the presence of the stent or re-enforcement elements or inthe presence of the stent, ability of the stent or other endoluminalprosthesis to further expand after deployment without having stentbreaks, separation, or discontinuities, ability of the lumen or vesselto positively remodel in the presence of the stent or other endoluminalprosthesis without having discontinuities, breaks, or separations.

In one example, the endoluminal prostheses of the present invention willtypically comprise scaffolds with circumferential structures such asrings which comprise a plurality of struts joined by crowns, commonlyreferred to as zig-zag stents, serpentine stents, closed cell designs,and the like. In accordance with a further aspect of the presentinvention, at least some of the struts in at least some of the zig-zagor serpentine rings will include at least one separation regionconfigured to form a discontinuity and/or uncage in the circumferentialring after expansion of the stent and/or strut in a physiologicenvironment. In these examples, the crowns of the rings and connectedlinks which joins adjacent rings are preferably free from separationregions. This allows for a controlled expansion of the individual ringsas well as of the stent as a whole in response to luminal remodeling.

In another example, endoluminal prostheses having separation regions inindividual struts of their circumferential rings will formdiscontinuities which allow the scaffold to uncage, and/or expand beyondan initial expansion after deployment in a target blood vessel or otherbody lumen. The physiologic environment in which the prostheses areexpanded will typically be physiologic conditions such as that of a bodylumen, such as a vascular environment which may be mimicked by a waterbath at 37° C. In the vascular environment, the discontinuities whichform in the rings will allow the scaffold to circumferentially uncage,and/or open as the blood vessel and/or lumen positively remodels afterplacement of the stent or other prosthesis. The discontinuities willtypically form in a period from 30 days to 6 months after the initialexpansion of the circumferential scaffold within the physiologicenvironment but can have such discontinuities form 1 day afterdeployment to 3 years after deployment. In one example thediscontinuities are formed and/or occur before implantation wherein suchdiscontinuities still allow for crimping, and/or allow for stentdeployment from a crimped configuration to an expanded configuration andhave sufficient strength to support a body lumen. In such case the stentor stent structures regions uncages, and/or allows for further expansionin at least said region of discontinuity of the stent structure.

In another example, the separation regions within the struts of thecircumferential rings may comprise “key and lock” or similar typejunctions in the struts and/or other structural elements, whichjunctions are held together and/or immobilized during expansion butconfigured to open or release after the initial expansion in thephysiologic environment. In one specific type of key and lock junction,the key and lock will open to allow the joined segments of the strut toseparate from each other in a radial direction only after the separationregion is free to separate (i.e. is mobilized). In other specificexample, the key and lock type junctions are configured to allow thejoined segments of the strut to separate from each other in both radialdirection and axial direction after they are mobilized. The key and lockjunctions type may be held together and/or immobilized by a polymer,coating, a sleeve material, cement, and/or adhesive which is applied toabutting surfaces of the junctions where the coating, cement, sleeve, oradhesive is selected to degrade in the physiologic environment overtime.

In another example of suitable adhesives, stent material, sleevematerial, coatings, and cements, include but not limited to polylactide;poly(L-lactide); poly(D-lactide); poly-DL-Lactide, polyglycolide;polylactide-co-glycolide (e.g., poly(L-lactide-co-glycolide) with 85%L-lactide to 15% glycolide); copolymer ofpoly(L-lactide-co-epsilon-caprolactone (e.g., weight ratio of from 50 toaround 95% L-lactide to about 50 to about 5% caprolactone; poly(L-lactide-co-trimethylene carbonate); polytrimethylene carbonate;poly(glycolide-trimethylene carbonate);poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids; protein such as elastin, fibrin, collagen,glycoproteins, gelatin, or pectin; poly-serine; polycaprolactam;cyclodextrins; polysaccharides such as chitosan, and hyaluronan;alginate; polyketals; fatty acid-based polyanhydrides, amino acid-basedpolyanhydrides; poly(ester anhydride); or the like; and combinationsthereof.

In other examples, the key and lock junctions type are held togetherand/or immobilized by an overlying sleeve or similar external structurewhich envelopes the junction and which prevents the junction fromcompletely and/or partially releasing and/or opening while the sleeveremains intact and/or substantially intact and/or non-degraded but whichdegrades in the physiologic environment over time in order to open andrelease the junctions.

In still other examples, the separation regions located within thestruts of the circumferential rings may comprise butt joints, notches orthinned regions within the struts, modified grain boundaries within thestruts, and the like, which preferentially erode or fatigue within thestruts, or any of the other specific separation regions describedelsewhere herein.

In further specific examples of the endoluminal prostheses of thepresent invention, a scaffold comprises circumferential rings patternedfrom a metal or other non-degradable material, where the scaffold isconfigured to expand from a crimped configuration to an expandedconfiguration. In these embodiments, at least some of thecircumferential rings comprise a plurality of struts joined by crownsand at least some of the struts have at least one separation regionwhich is pre-formed as a break in the structure of the strut, e.g.formed by laser or otherwise cutting across the strut as or after it hasbeen patterned, which is immobilized by a sleeve or an adhesive whichwill degrade in physiologic environment over time.

While the separation region examples may be any of those describedpreviously herein, a preferred separation region examples comprises akey and lock junction where the struts are held together and/orsubstantially held together or immobilized during expansion andconfigured to open after an initial expansion within the physiologicenvironment. The key and lock junction types in this example may beconfigured to allow the joined segments of the strut to separate fromeach other in a radial direction only after the joints are free.Alternatively, the key and lock junctions may be configured to allow thejoined segments of the strut to separate from each other in both aradial direction and an axial direction after the junctions are free,i.e. opened or released from constraint. In both cases, the key and lockjunctions may be initially immobilized by a cement or adhesive or asleeve or a coating which holds the budding surfaces of the strutsegments together or close together and which degrades in physiologicenvironment. Alternatively, the strut segments joined by the key andlock junctions may be immobilized by an overlying sleeve which degradesin the physiologic environment. Such junctions are immobilized,substantially immobilized, held together, substantially and/or heldtogether; to restrict or substantially restrict movement, in one or moredirections (preferably substantially restrict movement in an axialdirection) upon deployment from a crimped configuration to an expandedconfiguration Immobilization of such junction are accomplished using amaterial such as polymer, sleeve, or adhesive, or by the configurationof junction design.

In a preferred example, the stent (scaffold) prosthesis in thisinvention is formed from a substantially tubular body (said tubular bodyin a preferred example is substantially free from holes and/ordiscontinuities). The stent comprises structural elements capable ofradial expansion from a crimped configuration to an expanded deployedlarger configuration. The structural elements in a preferred examplecomprises a plurality of circumferential rings, said rings comprisingstruts joined (connected) by crowns. At least some of said rings areconnected to adjacent rings. The stent in preferred examples can becrimped onto a balloon delivery system or a delivery system (optionallyconstrained in the crimped configuration by a sleeve). The stent in apreferred example is balloon deployable and/or self-expanding stent. Thestent prosthesis can also be formed from a wire or a fiber (round orsubstantially round, square or substantially square, rectangle orsubstantially rectangle, and/or other shapes, wherein the wire or fiberis patterned into a stent capable of radial expansion from a crimpedconfiguration to a deployed larger configuration. The stent can also beformed from a hollow or partially hollow wire (having hollow regionswithin the wire or fiber) or fiber wherein the hollow or partiallyhollow wire or fiber is patterned into a stent capable of radialexpansion from a crimped configuration to a deployed largerconfiguration. The stent pattern in preferred examples can be serpentinerings, zig zag rings, diamond, interwoven and/or mesh pattern, closedcell design, open cell design, and/or combination thereof. Preferably,the stent shape in the deployed configuration is substantially tubular(cylindrical), tapered stent, hour glass stent, and/or other shapes. Therings, crowns, struts, dimensions (length, thickness, angle ofcurvature, width) are configured in to allow the stent to deploy(expand) and have the various shapes above.

One skilled in the art would appreciate the applicability of theembodiments and/or examples throughout this application to prosthesisacross various mammalian body applications where a stent prosthesis isimplanted, such as endoluminal prosthesis, outer-luminal prosthesis,annulus prosthesis such as valves comprising circular or other shapes,and/or other type of lumen, duct, annulus, cavities, sinus, etc. withina mammalian body.

In one example the stent prosthesis comprises a valve such as an aorticand/or mitral valve and/or tricuspid valve, wherein the stent prosthesiscomprising an expandable stent prosthesis (balloon expandable orself-expanding) wherein the stent circumferential structural elementssuch as for example struts joined by crowns (and/or including forexample a plurality of rings), or other type stents formed from a tube,a wire, a sheet, or a braided stent formed from one or more wires, andthe stent is configured into an open cell design pattern, a closed celldesign pattern, or combination of open cell and closed cell pattern, orother, and wherein the stent prosthesis comprises shape memory alloysuch as NiTi, and/or non-degradable metal or metal alloy such asstainless steel 316L or L605, or other materials described in thisapplication, or other, and wherein at least some struts (but can also becrowns, circumferential links/connector, or combination) in at least onering or at least one segment of the stent (a proximal segment, amid-segment, and/or distal segment, and/or regions within a segment)have at least one or more of: junctions, bridging elements, joints,discontinuities, and/or separation regions as described throughout thisapplication, which are configured to uncage, and/or configured to have adisplacement (or movement) in one or more directions or movementpattern, and/or configured to have radial strain, and/or configured tohave radial contraction and expansion, or configured to have inferiorcontraction and/or expansion, and/or configured to have superiorcontraction and/or expansion, after deployment of the stent prosthesiswithin, in, or around, or above, or adjacent to, an annulus of a bodyvalve, wherein the displacement magnitude (or radial strain magnitude,or contraction magnitude, or further expansion magnitude, or movementmagnitude) ranges from 0.05 mm to 10 mm, preferably ranges from 0.1 to 7mm, preferably ranges from 0.2 mm to 5 mm, more preferably ranges from0.3 mm to 3 mm, and wherein the displacement or radial strain movementis in at least one or more of the following: radial direction,circumferential direction, longitudinal direction, superior direction,inferior direction, valve leaflets closure direction, annulus (or lumen)contraction and/or expansion direction, or combination thereof, andwherein the stent prosthesis is substantially cylindrical, oblong,annulus shape, saddle shape, circular, or other shape to conform to theanatomy where the stent prosthesis is to be implanted in, wherein theseparation regions, junctions, bridging elements, gaps, joints, formdiscontinuities, and/or allow at least one or more structural elementsto have movement (displacement) in one or more direction such ascircumferential, radial, and/or longitudinal, or combination thereof (asformed, before implantation, and/or after implantation) wherein thestent prosthesis have sufficient strength to support (including hold, ormaintaining) the implantation site (including valve annulus, cavity))open, and/or have sufficient strength to hold (including maintaining) astructure associated with the implanted stent prosthesis in place(including the valve and/or sheath associated with the stent prosthesisas deployed or after deployment), wherein the stent prosthesis upondeployment (expansion from a crimped configuration to an expanded largerconfiguration) has sufficient strength to support the valve annulusand/or associated stent valve open and/or in place, and wherein saiddiscontinuities, and/or movement, allow uncaging, displacement,contraction, and/or further expansion, of at least one or at least someregions of at least one or at least some segments of the stentprosthesis or stent prosthesis structural elements, and/or saiddiscontinuities, and/or movement (displacement), allow expansion and/orcontraction of at least one or at least some regions of at least one orat least some segments of the stent prosthesis or stent prosthesisstructural elements, and/or said discontinuities, and/or movement, allowthe stent and/or at least one or at least some regions of the stent tobe less rigid (including more compliant (radial strain) in at least oneor more directions such as the circumferential direction, the radialdirection, the longitudinal direction, or combination thereof).

In a preferred example, the separation regions, junctions, bridgingelements, gaps, joints, are placed (including located) in a pattern thatallows for the stent (or at least some regions or segments of the stent)to have sufficient strength after deployment, and allows at least someregions or segments of the stent prosthesis (including thecircumferential regions of said stent regions) to uncage, to be morecompliant (radial strain) under physiologic conditions, to expand and/orcontract under physiologic condition, and/or prevent (includingminimize, reduce) blood leakage after stent (including valve)implantation. The prevention of the blood leakage can be minimized byhaving the stent in at least some region be and/or become more compliant(including less rigid) making the stent in at least said regions moreconformable to the anatomy the stent is implanted in as the anatomymoves or changes shape under physiological conditions (more dynamicallycompliant). The prevention of blood leakage can occur upon implantationor after implantation. The separation regions, junctions, bridgingelements, gaps, joints, can be placed in at least one ring, or at leastsome regions of at least one segment of the stent prosthesis such as theproximal segment of the stent, a mid-segment of the stent such as thesegment holding the valve, and/or a distal segment of the stent, and/orall three segments of the stent prosthesis. Optionally, a sheathsurrounding at least a region or segment of the stent prosthesis can beconfigured to respond (including contour, expand, adapt) to thecorresponding discontinuities, and/or movement of the stent prosthesisadjacent to the sheath region. The sheath can be configured and/orformed from stent like structure having separation regions, junctions,bridging elements, gaps, joints, and/or a sheath capable to adapt to theadjacent stent region in expansion and/or contraction or in other ways.In a preferred embodiment or example the stent prosthesis in at leastone ring or in at least some regions (preferably the entire stent)maintain sufficient strength after implantation, in other examples thestent prosthesis strength decreases over time after implantation rangingfrom 30 days to 3 years, preferably ranging from 3 months to 2 years,more preferably ranging from 6 months to 2 years. In this other examplethe residual strength is either sufficient strength to perform one ormore of the functions described and/or other functions, or the stentprosthesis in at least some regions (or all the stent) will have noresidual strength over the said time period ranges.

In one example, a stent prosthesis for valve replacement or repair,wherein the stent is substantially cylindrical or have other shapesconforming to the annulus where the stent is to be implanted in, andwherein the stent is patterned from a tube, a wire, or braided, andwherein the stent is balloon deployable or self-expandable, and whereinthe stent is configured to expand from a crimped configuration to anexpanded larger configuration, and have sufficient strength in theexpanded larger configuration to hold the annulus open (or to support anannulus). The stent prosthesis optionally comprises a valve (such asbicuspid or tricuspid) coupled to said stent prosthesis. The stentprosthesis optionally comprises at least one skirt on at least onesurface region such as the abluminal and/or luminal surface region ofthe stent prosthesis coupled to the stent prosthesis and/or theprosthetic valve. The at least one skirt in one example can also beweaved into the abluminal and/or luminal surface regions. The at leastone skirt in another example can be coupled to at least one segment ofthe stent prosthesis, such as a proximal segment of the stentprosthesis, a distal segment of the stent prosthesis, a mid-segment ofthe stent prosthesis, and/or the entire stent segments, on the abluminaland/or luminal surface regions. The at least one skirt in one examplecan have a pouch configured to swell or fill up with blood after thestent prosthesis implantation. In one example, the stent is configuredto have at least one segment (or region) of the stent to have at leastone or more of separation regions, discontinuities, bridging elements,junctions, joints, gaps, to allow uncaging and/or higher displacement inone or more of the following after expansion of the stent prosthesis:higher strain, higher displacement, higher contractility and/orexpandability, better valve closure, less valve leakage, betteraccommodation of valve closure when the heart is dilated, saiddisplacement in at least one segment and/or stent taking place in one ormore of: stent radial direction of the stent, stent circumferentialdirection, stent longitudinal direction, towards a superior direction ofthe stent, towards an inferior direction of the stents, and/or othertype directions or movements such as a saddle shape direction toaccommodate a mitral valve annulus. The at least one or more separationregions, discontinuities, joints, junctions, bridging elements, gaps,etc., are configured (or positioned, or located, or placed) along thedesired stent, stent segment, or stent region, to provide for therequired movement (or displacement). Examples for placement locations ofsuch uncaging and/or displacement features include: the stent segment(or region) adjacent to the synthetic valve, attached at least in partto the synthetic valve in at least one region, placement in amid-segment of the stent prosthesis, placement in a distal segment ofthe stent prosthesis, placement, placement in a proximal segment of thestent prosthesis, placement on at least one side of at least one segmentof the stent prosthesis, placement on one half side of at least onesegment of the stent prosthesis (while the other half of said segment isfree from such uncaging features) in a cylindrical shape stent forexample, or combination thereof. The at least one segment havingdisplacement magnitude in at least one direction in one example rangingfrom 0.1 mm to 10 mm, preferably ranging from 0.2 mm to 7 mm, morepreferably ranging from 0.35 mm to 7 mm. The stent prosthesis optionallyhave supporting features (such as additional struts joined by crownswithin the stent prosthesis rings) to further provide strength, support,or other mechanical properties, to the main stent prosthesis structuralelements. The supporting features can have uncaging features or be freefrom uncaging features. The stent prosthesis in this example hassufficient strength in the expanded configuration to support a bodyannulus (or to maintain a body annulus open, or to hold the stent in abody annulus in place) while providing after expansion one or more of:higher (or larger or increased) radial strain (or compliance), larger(or higher or increased) displacement, higher (or increased) compliance,larger contraction and/or expansion, in at least one stent segment (orregion) of the stent prosthesis compared to an adjacent stent segment(or region), or the stented segment, under physiological conditions.

In one example, an implant having length, width, and thickness, isattached (or held in place) adjacent to a body lumen or a body annulus(or within a body lumen or within a body annulus) and wherein theimplant is configured to be coupled with (or attached) to an expandableprosthesis, and wherein at least one of the implant and the stentprosthesis are configured to have one or more of separation regions,junctions, joints, hinges, bridging elements, gaps, on at least onesegment or region of the implant and/or stent allowing the at least onesegment or region of implant and/or stent to have displacement, in oneor more directions, that is larger than an adjacent segment (or region)of the said implant or stent prosthesis, under physiological conditions.

In one example, an implant having length, width, and thickness, isattached (or held in place) adjacent to a body lumen or a body annulus(or within a body lumen or within a body annulus) and wherein theimplant is configured to be coupled with (or attached) a prosthetic (ornatural) valve, and wherein at least one segment or region of theimplant is configured to have one or more of separation regions,junctions, joints, hinges, bridging elements, gaps, allowing the atleast one segment or region of implant to have displacement, in one ormore directions, that is larger than an adjacent segment (or region) ofthe said implant, and wherein said displacement is configured to allowthe valve to operate (or to function or to open and close) underphysiological conditions, or allows (or enhance) the valve to conform(or contour) to the annulus or deformed annulus preserving the functionof the valve.

In another example, a stent prosthesis formed from a shape memorymaterial, or formed from a spring (or coil) material, and is patternedfrom one or more wires into a braided pattern, or is patterned from atube into a closed cell type design or an open cell type design, or ispatterned from a wire into a closed cell type design or an open celltype design, or combination thereof, and wherein the stent isself-expandable from a crimped configuration to an expanded largerconfiguration and have sufficient strength to support a body annulus,and wherein the stent prosthesis is coupled to a valve, said stenthaving one or more of separation regions, junctions, hinges,discontinuities, in at least one segment: distal, proximal, or adjacent,to the coupled valve, and wherein said segment after expansion andformation of discontinuities (or after uncaging) has lower outwardradial force while the stent is in the expanded configuration butsmaller than the nominal or maximum expansion diameter force, preferablybetween 5-15% smaller than the maximum expansion diameter outward force,more preferably between 15% and 75% smaller than the nominal or maximumexpansion diameter outward force.

In preferred example, the composite radial strain/compliance (or vesseldilation under pressure or therapeutic drug such as nitroglycerine) inone example of the stent prosthesis having at least one or moreseparation regions forming discontinuities after expansion ranges from1% to 10%, or from 1% to 5%, preferably ranges from 1.5% to 4%, and/orhas a diameter change ranging from 0.03 mm to 3 mm, preferably rangingfrom 0.05 mm to 0.15 mm, or more preferably ranging from 0.07 mm to 0.15mm, or most preferably ranging from 0.1 mm to 0.3 mm, under physiologicconditions or simulated physiologic conditions. The pattern ofseparation regions can be configured for example to adapt to the anatomythe stent prosthesis is implanted in to accommodate the forces of suchanatomy and/or dynamic movement and thereby comprising one or moreplanes to uncage or allow movement (and/or expand, etc) ranging fromcircumferential to axial planes and/or in between, and/or radial. Oneskilled in the art would appreciate the application of these embodimentsto balloon expandable stents and/or self-expanding stents, includingopen cell designs, closed cell design, coil design, or weaving stentpatterns, etc. In another example the stent prosthesis uncages, and/orallows movement, and/or further expands, and/or have higher radialstrain (compliance), and/or etc., upon deployment or after deployment byincorporating other means described in this application.

In a preferred embodiment or example where in many instances an implantsuch as s stent prosthesis is implanted to open, hold open, to hold inplace, to support, to repair and/or replace a malfunctioning structuresuch as a valve, or other; the stent in such instances are implanted ina variety of anatomy such as an artery, a vein, a duct, a valve annulus,sinus, cavity, and/or other mammalian body lumen, where such artery, avein, a duct, a valve annulus, sinus, cavity, and/or other mammalianbody lumen, are usually undergoing various physiologic conditions suchas pressure, pulsating pressure (systole and diastole), movements (ordisplacement) in one or more planes/directions, shaping and/or reshapingof said lumen or annulus, expansion and/or contraction, forces from oneor more planes/directions, where the implant is desired to havesufficient strength at least upon implantation to open, hold open,support, repair and/or replace a malfunctioning structure; and at thesame time, and/or over time after implantation the implant/stent isdesired to have the ability to comply with (accommodate, and/or toconform) at least partially to the physiological conditions of movements(displacement), forces, expansion and/or contraction, shaping orre-shaping of the lumen, etc thereby preserving the function of theimplant and the integrity of the stent support (or valve containedwithin the stent). The implant prosthesis described throughout thisapplication allows the artery, vein, duct, cavity, annulus, and/or otherbody lumen, to at least partially restore (or accommodate or comply withat least partially) some of said movement (displacement), expansionand/or contraction, forces, and/or shaping or re-shaping of lumen;thereby reducing and/or preventing the unwanted effects of an implantand thereby reducing and/or preventing unwanted adverse events such asnarrowing and/or re-narrowing of a lumen, restenosis, blood leakage,occlusion, thrombus formation, angina, ischemia, aneurysm, etc., thestent as described throughout this application allows at least one ormore regions, and/or at least one segment (and/or the entire stent) touncage, to allow to move, to expand, to further expand, to furtherexpand from the deployed/expanded configuration, to shape and/orre-shape into a new configuration from the deployed configuration, toexpand and/or contract, to have a radial strain (compliance) closer tothe natural radial strain (compliance) of the lumen (and/or anatomywhere the stent is implanted in), to have a higher radial strain(compliance) than immediately after deployment radial strain/compliance(or before forming discontinuities in some cases), to accommodate atleast some of the lumen (annulus, cavity etc.,) physiological conditions(including dynamic movement/displacement, and/or dynamic forces, and/ordynamic expansion and/or contraction, and/or dynamic shaping and/orre-shaping), and/or to lessen the resistance of the implant (stent) tothe physiologic conditions of the implant site, and/or to providesufficient stent structure after deployment (or after formation of thediscontinuities) to protect body lumen, protect vessel lumen, supportbody lumen, and/or support vessel lumen, from potential harmful plaquesuch as vulnerable plaque. The stent after formation of discontinuitiesmaintains sufficient stent structure which can have radial strength, orno radial strength after formation of discontinuities and/or afterdeployment.

In a preferred example, the stent prosthesis is formed from and/orcomprises a non-degradable material that has high radial strength (forexample sufficient to support a body lumen upon deployment of thestent), wherein the material is preferably a metal or metal alloy butcan also be a polymer, or other material of high radial strength upondeployment. In a preferred example non-degradable material does notdegrade within at least five years from implantation in a body lumen (orunder physiologic conditions), preferably does not degrade within atleast ten years from implantation in a body lumen (or under physiologicconditions, more preferably does not degrade within at least 20 yearsfrom implantation, and/or within at least 50 years from implantation.Examples of non-degradable metal or metal alloys include but not limitedto the following: stainless steel alloys such as 304 stainless steel(including 304V and 304L), 316 stainless steel (including 316 L and 316LV), stainless steel alloys having % Fe by weight ranging from 30% to80%, Cobalt alloys such as Cobalt Chrome including L605, MP 35, cobaltalloys having % Co by weight ranging from 25% to 60%, Platinum alloysincluding platinum alloys having % Pt by weight ranging from 25% to 40%,metal alloys having Chrome in the alloy including alloys having % chromeby weight ranging from 15% to 25%, Mo—Re based alloys (includingIcon-Nuloy alloy), Tantalum and Tantalum alloys, gold and gold alloys.Tungsten and Tungsten alloy and/or silver and silver alloys, arecorrodible (degradable) metals.

The words corrodible and degradable are used interchangeably in thisapplication.

In another example, the expandable stent having separation regions,and/or other configurations as described throughout this application,wherein at least some regions of the stent form discontinuities afterdeployment, uncage upon or after deployment, expand further, have higher(or increased) radial strain, allow less resistance to the implant siteor lumen, and/or have the strength decreases ater implantation, whereinat least said regions of the separation regions (and/or otherconfigurations) maintain substantially their position within the stentprosthesis structural elements after expansion, protrude (or move)outwardly from the stent prosthesis structure, protrude (or move)inwardly from the stent prosthesis structure, move in an adjacent way(or direction) to the stent prosthesis, and/or combination of the above,after deployment of the stent and/or after forming discontinuities.

In another example the stent prosthesis in any of the examples describedthroughout this application, wherein the stent prosthesis upondeployment has sufficient strength to support a body lumen (and/or holdin place a valve while maintaining a body lumen (such as valve open) andwherein the strength is substantially maintained after deployment(and/or after forming discontinuities). In another example, the strengthafter deployment decreases in a step function (or the strength decreasesas step function after deployment, and/or the strength decreases afterforming discontinuities) within 30 days, preferably within 3 months,more preferably within one year). In yet another example, the strengthafter deployment decreases in a gradual manner, and/or decreases in alinear decay manner, within 30 days, preferably within 3 months, morepreferably within one year, after deployment (and/or after formingdiscontinuities). In yet another example the stent prosthesis strengthafter deployment (and/or after forming discontinuities) decreases, saiddecreased strength sufficient to support a body lumen (and/or hold astructure in place, and/or hold a lumen or annulus open). In yet anotherexample the stent prosthesis strength after deployment (and/or afterforming discontinuities) decreases and reaches a plateau, said plateaustrength sufficient to support a body lumen (and/or hold a structure inplace, and/or hold a lumen or annulus open). In yet another example thestent prosthesis strength after deployment (and/or after formingdiscontinuities) decreases but does not reach zero. In yet anotherexample the stent prosthesis strength after deployment (and/or afterforming discontinuities decreases to zero within one months, within 3months, and/or within one year. In a preferred example, the stent havingdecresed strength compared to initial strength but larger that zerostrength, or having zero strength, maintains (or has) a sufficientcircumferential structure to support a body lumen.

In another example of any of the examples of this application,preferably wherein the stent prosthesis comprises and/or formed from anon-degradable material such as non-degradable metal or metal alloy, thestent prosthesis upon deployment from crimped configuration to anexpanded larger configuration has, low inward recoil, preferably zeroinward recoil to low inward recoil, preferably zero inward recoil to 6%inward recoil, more preferably zero inward recoil to 10% inward recoil,when deployed/expanded from the crimped configuration to the expandedconfiguration/diameter. In another example the stent prosthesis afterdeployment (after initial recoil (if any)) has substantially zero inwardrecoil to 3% inward recoil from the expanded configuration (preferablyhas substantially zero inward recoil), within 30 days after deployment,preferably within 60 days after deployment, more preferably within 3months after deployment. In another example, the stent prosthesis afterdeployment from a crimped configuration to an expanded largerconfiguration (after initial recoil (if any)) and/or after formingdiscontinuities, further expands (on its own or unaided) to a largerconfiguration, further expands to a larger configuration larger than theexpanded configuration after recoil, and/or further expands to a largerconfiguration larger than the deployed configuration (before initialrecoil). The stent prosthesis in the example further expands within 360days, preferably within 270 days, more preferably within 6 months, morepreferably within 3 months, most preferably within one month, fromdeployment and/or implantation. In another example the stent prosthesisafter deployment and/or after forming discontinuities, will expandand/or contract by a total magnitude of 2%-15% of the deployeddiameter/configuration (after initial recoil (if any)), preferably by atotal magnitude of 3% to 10% of the deployed diameter/configuration(after initial recoil (if any)), or more preferably by a total magnitude4% to 15%) of the deployed diameter/configuration, within one monthafter deployment, preferably within 3 months after deployment, morepreferably within 6 months after deployment, most preferably within oneyear after deployment.

In another example the stent prosthesis having separation regions(and/or other configurations describes throughout this application) asdescribed throughout this application, preferably wherein the stentprosthesis comprises and/or formed from non-degradable material such asnon-degradable metal or metal alloy, wherein the stent after deploymentforms at least some discontinuities in at least some circumferentialstructural elements separation regions, and wherein the stent prosthesisafter deployment (and/or after forming said discontinuities)substantially maintains the stent prosthesis structure and/or shape. Inanother example, the stent prosthesis substantially maintains the stentprosthesis circumferential structure and/or shape. In yet anotherexample the stent prosthesis after deployment (and/or after forming saiddiscontinuities) substantially maintains the stent prosthesis deployedconfiguration. In yet another example the stent prosthesis afterdeployment (and/or after forming said discontinuity/discontinuities) hasno more than one discontinuity per any ring (or per at least somerings), preferably no more than two discontinuities per any ring (or perat least some rings), more preferably no more than three discontinuitiesper any ring (or per at least some rings), more preferably no more thanfour discontinuities per any ring (or per at least some rings). Thestent prosthesis having separation regions forming discontinuities inone example along the length of the stent prosthesis in a substantiallystraight, or helical, or other shape, along the stent length, slicingthe stent in this example along the longitudinal stent length (whilemaintaining intact one, some, or all or axial links connecting (joining)adjacent rings) in straight, helical, or other configurations. Inanother example, the stent prosthesis forming discontinuities slicingthe substantially cylindrical stent structure along (or extending) thelength of the stent prosthesis (while maintaining intact one, some, ormore axial links connecting (joining) adjacent rings) into twostructures or segments (such as two circumferential semi circlesstructures along (or extending) the stent length), In another examplethe stent prosthesis forming discontinuities slicing the substantiallycylindrical stent structure along the length of the stent prosthesis(while maintaining intact one, some, or all axial links joining adjacentrings) into three structure (such as three partial circumferentialstructures extending along the stent length). In another preferredexample, the separation regions and/or discontinuities are located ontostrut structural elements, such that no more than one separation regionand/or discontinuity per strut (or per some struts), and no separationregions and/or discontinuities on crowns, and/or no separation regionand/or discontinuities in regions joining struts to crowns. In anotherpreferred example, the separation regions and/or discontinuities arelocated at least within a strut region of a ring(s), or substantially inthe middles of struts, or along the length of the strut (away from thecrown and/or away from the junction joining the strut to the crown),and/or located in regions that are substantially non deformable or lessdeformable of the ring, and/or located in regions that have less or hasreduced stress forces of a ring as the stent expands from a crimpedconfiguration to an expanded deployed configuration, and/or located inregions that are substantially non deformable or less deformable on aring when the stent expands from the crimped configuration to anexpanded configuration, and/or located in regions where the separationregions are substantially maintained together (or substantially heldtogether) upon deployment of the stent, on a ring, from a crimpedconfiguration to an expanded configuration.

In another example, the separation regions have (or defines, orcomprises) a gap between the two opposite ends of the structuralelements adjacent to the separation, and/or between the two adjacentends of the structural element adjacent to the separation region (forexamples the two ends of the non-degradable metal alloy containing ordefining or comprising a separation region). The gap width ranges fromzero to 50 microns, preferably ranges from zero to 30 microns, morepreferably ranges from zero to 15 microns, more preferably rangesbetween zero and 10 microns, most preferably ranges from 5 micros to 30microns. The gap can be filled with a coating such as a degradablepolymer coating. The coating can extend beyond the separation region tofurther hold in place the separation regions upon deployment of thestent from a crimped configuration to an expanded larger configuration.

In a preferred example, the stent prosthesis comprises structuralelements, preferably circumferential structural elements comprisingplurality of rings, each ring comprises struts joined by crowns, andeach ring is connected to an adjacent ring (or non-adjacent ring)through (or by) a link or joined directly without a link. The stentprosthesis is expandable from a crimped configuration to an expandedconfiguration to support a body lumen and/or to hold a lumen open and/orto hold a structure (connected or attached to the stent) in place. Thestent prosthesis can have a sheath surrounding and/or attached to thestent or at least a segment of the stent (preferable in acircumferential direction). The stent can hold in place (and/or attachedbefore deployment or after deployment) a structure such as a valve(synthetic or biologic). The stent can also have means to anchor thestent or regions within the stent to body lumen, tissue, etc. The stentcan also have tendons or wires attached to some regions of the stent toanchor the stent or pull it inwardly from at least one region orsegment. In another example, the stent comprises one circumferentialstructural element comprising. In another example the stent prosthesiscomprises one ring, said ring comprises struts joined by crowns. Inanother example, the stent and/or implant comprises a structure capableof expansion from a crimped configuration to an expanded largerconfiguration.

In another example, the coating thickness, and/or sleeve thickness,covering at least part of the separation regions, and/or crowns, rangesfrom 3 microns to 100 microns, preferably ranges from 5 microns to 50microns, more preferably ranges from 10 microns to 50 microns. Thecoating, sleeve, material can be degradable or non-degradable such asdegradable polymer or non-degradable polymer. In case of non-degradablepolymer example, such as parylene or C-flex or polyurethane, in oneexample the polymer contains (holds together) the separation regiontogether within the epolymer, wherein the separation region and/ordiscontinuity after deployment is allowed to uncage and/or separate(form discontinuities) within the non-degradable polymer (i.e. thenon-degradable polymer continues to encapsulate the separation regionand/or discontinuity), but allows the stent and/or stent region touncage, and/or further expand, and/or become more compliant, or haveincreased compliance after formation of discontinuities.

In a preferred example in any of the examples in this application, thestent prosthesis is capable to expand from a crimped configuration to anexpanded larger configuration without coming apart, and/or is capable toexpand from a crimped configuration to an expanded larger configurationwhile maintaining structural integrity, and/or is capable to expand froma crimped configuration to an expanded larger configuration whilemaintaining the separation regions being held together, and/or iscapable to expand from a crimped configuration to an expanded largerconfiguration while maintaining the discontinuities being held together.The expansion from crimped configuration to an expanded configurationranges from deployment to nominal stent diameter to 3 mm above nominalstent diameter, preferably ranges from nominal stent diameter to 2 mmdiameter above nominal stent diameter, more preferably ranges fromnominal stent diameter to 1 mm above nominal stent diameter. Nominalstent diameter includes nominal delivery system balloon diameter,labeled delivery system balloon diameter, nominal delivery systemlabeled diameter, and/or labeled delivery system diameter.

In one example the measurements of any parameter such as strengthcompliance, diameter, configuration, recoil, displacement, dimensions,etc., such measurements are specific measurements of one sample, mean ofmultiple samples, mean of multiple samples from one lot, mean frommultiple samples from multiple lots, and/or measurements from differentsamples (for examples testing strength) where the samples are built tothe same or similar specifications. In another example the measurementis the mean of multiple measurements, examples include the mean lumenarea representing measurement for lumen area, mean stent diameterrepresenting stent diameter measurement, etc. In another example,standard testing methods or commonly used test methods known to thoseskilled in the art can be utilized for the various tests such asdimensions, size, radial strength, recoil, expansion, contraction,diameters, radial strain (or compliance), resistance, etc., it is alsoapplicable for example to utilize IVUS, OCT, MSCT, QCA, or othermeasurements apparatus to measure bench, in-vitro, and/or in-vivomeasurements. Measurements can also be on bench, in-vitro, ex-vivo, orin-vivo. Measurements can also be on the stented segment, the segmentsof the stent ring having separation region(s), a proximal stent segment,a mid stent segment, and/or a distal stent segment.

In one example, a stent prosthesis comprising a non-degradable material(such as polymeric material) which has been patterned into a stentcomprising structural elements comprising rings, said rings compriseexpansion regions (such as crowns), and struts, wherein at least somereinforcement elements (such as metallic non-degradable) are coupled toat least some expansion regions of the non-degradable stent, and atleast some rings have at least one separation region, and wherein thestent prosthesis expands from a crimped configuration to an expandedlarger configuration and have sufficient strength to support a bodylumen, and wherein the separation region forms discontinuity on saidrings after implantation allowing the stent to further expand in aphysiologic environment.

In an example, metallic stent prosthesis are formed from a tube, or awire (solid, or hollow at least in certain region of the wire(preferably hollow in the non-deformable regions of the wire) andpatterned into a structure expandable from a crimped configuration to anexpanded larger configuration. The stent structure in one examplecomprises plurality of rings (and at least some rings having one or moreseparation regions) composed of structural elements of struts andcrowns, non-deformable elements (or substantially non deformableelements) such as struts, and deformable elements such as crowns. Atleast some of the rings are connected to adjacent rings in at least oneregion by for example a link. The metallic stents can also be formedfrom a patterned sheet that is then rolled into a tube and joinedforming a stent. In yet another example, the stent prosthesis can beformed by 3-D printing.

In another example, a polymeric stent prosthesis is formed from a tubeby spraying, extrusion, dipping, molding, or 3-D printing, and patternedinto a stent. Alternatively, the stent prosthesis can be formed from oneor more fibers or filaments and patterned or woven into a stent.

In a preferred example, the stent prosthesis is configured to uncageupon or after deployment, to exhibit vaso-dilation in a body lumen afterdeployment, to further expand to a larger configuration afterdeployment, and/or to have a radial strain ranging between 1% and 10%,preferably to have radial strain ranging between 1% and 7%, over (or onor across or along) substantially the entire stent segment, the stentsegment, the stent length, the stent circumferential diameter, and/orthe stent. In another example, the stent prosthesis is configured uncageupon or after deployment, to exhibit vaso-dilation in a body lumen afterdeployment, to further expand to a larger configuration afterdeployment, and/or to have a radial strain ranging between 1% and 10%,preferably to have radial strain ranging between 1% and 7%, over (or onor across or along) at least one segment of the stent, at least oneregion of the stent, at least some stent length, at least some stentcircumferential diameter, and/or the stent.

In a preferred example, the stent prosthesis for coronary arteriesapplication is configured to have one or more of the following in atleast some rings, preferably in substantially all rings: reinforcementelements reinforcing a degradable ring structural elements (frame) ofthe stent (strut and/or crown), bridging elements bridgingnon-degradable ring structural elements (frame) of the stent (strutand/or crown), separation regions in a non-degradable ring structuralelements (frame) of the stent, gaps in non-degradable ring structuralelements (frame) of the stent, and/or discontinuities on overlapping ornon-overlapping non-degradable ring structural elements (frame) of thestent (struts and/or crowns). The stents are configured to have 10% flatplate compression initial strength ranging from 0.025 N/mm of stentlength (0.45N for a 3.0 mm by 18 mm stent length for example) to 0.07N/mm stent length or higher (up to 0.3 N/mm stent length) after initialexpansion, and the stents is configured to have dimensions range from 60microns thick to 130 microns thick, while the width dimension rangesfrom 60 microns wide to 150 microns wide. The inward recoil isconfigured to range from 1% to 10%, and is substantially maintainedafter expansion (deployment). The stents are deployed in water at about37° (or in a body lumen) and tested either in water or in air afterexpansion (deployment). The stents are configured to uncage upondeployment or after deployment, expand to a larger configuration afterthe inward recoil, and/or exhibit vaso-dilatation (or allow the stentedbody lumen to exhibit enlargement (or expansion or further expansion)after introduction of a vasodilator in the body lumen, when the stent isdeployed (or expanded) in a body lumen. The stents are expandable from acrimped configuration to an expanded larger configuration withoutfracture. The stent has sufficient strength to support a body lumen. Ina preferred example, the stent has sufficient strength to support a bodylumen without additional recoil after initial inward recoil afterexpansion (deployment), when the stent is expanded in water at about 37C or in a body lumen.

In a preferred example of any aspect, example, or embodiment of thisinvention, the stent prosthesis has sufficient strength to support abody lumen ranging from 0.025 N/mm stent length to 0.07 N/mm of stentlength, preferably ranging from 0.04 N/mm stent length to 0.3 N/mm ofstent length.

In another example, at least some struts and/or crowns, on at least somerings are configured to have one or more of discontinuities, separationregions, bridging elements, and/or reinforcement elements. At least onediscontinuity, separation region, bridging element, and/or reinforcementelement, are configured or formed on the said each strut, and/or eachcrown, of the at least some rings, or combination thereof.

In another example, the stent comprising structural elements, said stentpatterned in a closed cell type design, a diamond shape rings, mesh typestent design, coil type design, and/or weaved (or braided) type stentdesign. The stent circumferential structural elements (such as rings)are configured to have one or more of discontinuities, separationregions, bridging elements, and/or reinforcement elements, and/orcombination thereof, sufficient to uncage the stent circumferentiallyafter expansion in a body lumen, to exhibit vaso-dilation in a bodylumen after deployment, to further expand to a larger configurationafter deployment, and/or to have a radial strain ranging between 1% and10%. The stent upon deployment to the expanded larger configuration hassufficient strength to support a body lumen.

In a preferred example of any aspect, example, or embodiment of thisinvention, the stent prosthesis has an initial inward recoil after thestent is deployed (expanded) from a crimped configuration to an expandedlarger configuration, where the initial inward recoil is substantiallymaintained, after the stent is expanded in water at 37C (or after thestent is expanded under physiologic conditions, or after the stent isexpanded in a body lumen). The stent initial recoil is measured within 1minute after deployment (expansion) of the stent, or the stent initialrecoil is measured within 5 minutes after deployment (expansion) of thestent. The inward recoiled is substantially maintained after deployment,maintained after deployment for at least 30 minutes, for at least 1hour, or for at least 1 day. In all cases in this example, the stentinward recoil is measured after deployment and deflation of thedeploying balloon or deploying means. The stent prosthesis in a mostpreferred example further expands after said initial recoil over aperiod ranging from 1 minute to 1 year or more, preferably over a periodranging from 30 minutes to 1 year or more, wherein the stent furtherexpansion configuration is less than the initial recoil magnitude,preferably larger than the initial recoil magnitude (or diameter or meandiameter), or more preferably wherein the stent further expansionconfiguration is larger than the deployed (expanded) stent configurationmagnitude (or diameter or mean diameter). In a preferred example thestent prosthesis comprises non-degradable metal or metal alloycomprising a plurality of rings.

In another example of any of the examples, the stent prosthesis has atleast one, or some links that connect (or join) at least some adjacentrings, wherein the one or some links remain substantially intact (orremain intact) upon, or after expansion (deployment), or after formationof all discontinuities. In another example, all the stent prosthesislinks remain intact upon or after expansion (deployment). In anotherexample, at least some rings (or substantially all rings) are connectedto adjacent rings in at least one region (or at least by one connectionor by at least one link) and where the at least one connection remainssubstantially intact upon or after deployment or after formation ofdiscontinuities. In another example, at least some rings are connectedto adjacent rings in at least two regions (or by at least twoconnections, or by at least two links) and where the at least twoconnection remains substantially intact upon or after deployment orafter formation of all discontinuities. In yet another example, at leastone link, preferably at least some links (or connections), joining atleast some rings are configured to have one or more of reinforcementelements. The stent prosthesis in this examples is also configured tohave at least some struts and/or crowns on at least some rings havingone or more of reinforcement elements. In yet another example,substantially all links (or connections), joining at least some ringsare configured to have one or more of reinforcement elements. The stentprosthesis in this example is also configured to have at least somestruts and/or crowns on at least some rings having one or morereinforcement elements.

In an example of any of the examples in this application, the stentprosthesis (or at least one segment of the stent prosthesis) isconfigured to have high crush resistance after deployment (or expansion)from a crimped configuration to an expanded larger configuration, wherethe stent circumferentially uncages, the stent circumferentially uncagesthe stented segment, further expands to a larger configuration, respondsto a vaso-dilator introduction, and/or has a radial composite strain (orcompliance) in the range of 1.5% to 7%, after expansion. The stentprosthesis in a preferred example substantially maintains the initialhigh crush resistance after expansion. The stent prosthesis in anotherexample exhibits a reduction (decrease) in crush resistance over aperiod of time ranging from after deployment and 1 year, where the crushresistance decreases ranges from 20% to 80%, over a period of timeranging from one month to one year, said remaining crush resistance issufficient to support a body lumen. In yet another example the stentprosthesis exhibits a decrease in crush resistance after deployment froma period of time ranging from after deployment and one year, said stentprosthesis after said period of time substantially has no crushresistance.

In a preferred example of any of the examples in this application, thestent prosthesis has a patterned structure after deployment (expansion),where the structure is substantially maintained (or intact, orsubstantially intact). In another example, the stent prosthesis has aninitial patterned structure after deployment (expansion), where theinitial patterned structure changes (or becomes different or ismodified) after expansion. In another example, the stent prosthesis hasa patterned structure comprising structural elements (comprising in apreferred example struts, crown, and links (or connections), wherein thestent after deployment (expansion), maintains (or has) at least onelongitudinal structural elements segment along substantially the lengthof the stent. The longitudinal structural element segment has (orcomprise) one or more breaks, separation regions, and/or discontinuitiesalong the longitudinal segment (excluding the link or connection regionswhich are axial connectors and which remains intact). The longitudinalsegment circumference in one example ranges from ¼ the circumference ofthe stent to ½ the circumference of the stent. The longitudinal segmentspattern can be substantially straight along substantially the length ofthe stent, or can be helical along the stent length, or otherlongitudinal pattern along the length of the stent. The at least onelongitudinal structural elements segment remains substantially intact(preferably remains substantially intact through the one or more links(or connections) along the length of the stent). In another example, thestent prosthesis has a patterned structure comprising structuralelements (comprising in a preferred example struts, crown, and links (orconnections), wherein the stent after deployment (expansion), maintains(or has) at least one circumferential structural elements segment alongsubstantially the circumference of the stent. The circumferentialstructural element segment has (or comprise) one or more breaks,separation regions, and/or discontinuities along the circumferentialsegment (excluding the link or connection which are axial connectors andwhich remains intact). The number of circumferential segments in oneexample ranges from 1 to 4. In another example, the stent prosthesis hasa patterned structure comprising structural elements (comprising in apreferred example struts, crown, and links (or connections), wherein thestent after deployment (expansion) maintains at least onecircumferential segment along the stent circumference and/or at leastone longitudinal segment along the stent length, wherein the segmentcomprises at least one crown and at least two struts, preferablycomprises at least one crown and at least two struts and at least onelink (or connection) remain intact or connected, more preferably,comprises two or more rings, partial rings (or ring regions). Thesegment has at least one separation region, break, and/or discontinuityon at least some rings (or partial rings or ring regions).

In another example, a stent comprising a degradable (includingcorrodible) material, wherein the material degrades in a period rangingfrom 1 year to 20 years, preferably from 2 years to 15 years, morepreferably from 3 years to 10 years, wherein the material is patternedinto a stent comprising structural elements, said structural elementscomprising a plurality of rings, each ring comprises struts and crowns.At least struts and/or crowns, on at least some rings have one or moreof separation regions, discontinuities, breaks, gaps, and/or bridgingelement, and wherein the stent prosthesis uncages after expansion from adeployed configuration to an expanded larger configuration. The stent inone example uncages upon deployment. The stent in another exampleuncages from a period ranging from 1 month to one year. The degradablematerial comprises one or more of a metal or metal alloy, a polymericmaterial, or other material that degrades from 1 year to 20 years. Thestent prosthesis upon expansion has 10% flat plate crush resistanceranging from 0.025 N/mm stent length to 0.085 N/mm of stent length, butcan also range from 0.05 N/mm to 0.2 N/mm of stent length.

In another example, a stent prosthesis comprising structural elements,said structural elements comprise a plurality of rings, each ringcomprises struts, crowns, and each ring is connected to an adjacent ringby at least one link (or connection), at least some struts and/or crownson at least some rings have one or more of separation regions, bridgingregions, discontinuities, gaps, and/or breaks, or combination thereof.In another example, a stent prosthesis comprising structural elements,said structural elements comprise a plurality of interconnected rings,substantially all rings have one or more of separation regions, bridgingregions, reinforcement element, discontinuities, gaps, and/or breaks, orcombination thereof. In yet another example, a stent prosthesiscomprising structural elements, said structural elements comprise aplurality of interconnected rings, at least half of all rings have oneor more of separation regions, bridging regions, reinforcement element,discontinuities, gaps, and/or breaks, or combination thereof.

In another example, a stent prosthesis comprises structural elements,said structural elements comprises a plurality of rings each ringcomprises struts and crowns, said stent prosthesis is plasticallydeformable from a crimped configuration to an expanded largerconfiguration, where the stent in the expanded larger configuration hascomposite radial strain (or compliance) ranging between 1% and 5%. Thestent in the expanded configuration is crush resistant and havesufficient strength to support a body lumen. The stent in preferredexample further expands to a larger configuration after deployment andafter an inward recoil (if any). The stent in another preferable exampleis plastically deformable over a range of diameters ranging from 1 mm to2 mm diameter range, preferably ranging from 2 mm to 4 mm diameterrange, more preferably ranging from 3 mm to 4.5 mm diameters.

In another example, a stent prosthesis as in any of the examples,wherein the stent prosthesis is delivered to a body lumen without arestrain (or sleeve), said stent expands from a crimped configuration toan expanded larger initial configuration, then said stent exhibitsinward recoil, before expanding to a second configuration (smaller orlarger than initial configuration).

In another example or aspect of this invention, a stent prosthesiscomprised of metal and metal alloys material wherein the stentprosthesis is expandable from a crimped configuration to an expandedlarger configuration and has sufficient strength to support a body lumenupon (or after) expansion. The stent material is pre-formed, or treated,and/or configured to exhibit one or more of the following afterexpansion: softening of the material, weakening of the material,becoming less stiff, has reduced crush resistance, has reduced strength,and/or has no strength, has an initial strength sufficient to support abody lumen wherein the strength decreases over time, has an initialstrength sufficient to support a body lumen wherein the strength remainssubstantially the same over time, and/or has an initial compliance uponexpansion and wherein the compliance increases after expansion, and/orhas an initial compliance immediacy after expansion (or within 24 hoursafter expansion) and wherein the compliance increases after expansion(or within 6 months after expansion), under one or more of the followingconditions: physiologic conditions (which also includes one or more ofthe following): in water at 37 C, cyclic physiologic fatiguing(pulsation), and/or physiologic temperature, in a period ranging from 1month to 5 years, preferably ranging from 3 months to 3 years, morepreferably ranging from 3 months to 2 years, after expansion, pressuredifferential ranging from 50 mmHg to 200 mmHg. The stent materialtreatment comprises, heat, quenching, cyclic fatiguing, or other, saidtreatment taking place at one or more of the following: before forming,during forming, after forming, before stent patterning, or after stentpatterning. The stent after expansion exhibits one or more of thefollowing: being further expandable to a larger configuration, expandsfurther in response to vaso-dilator introduction, and/or has a compositeradial strain (or compliance) ranging from 1.5% to 5%, in water at 37 C,or under physiologic condition, and/or in a body lumen.

In another example, the stent material comprises, or composed of, one ormore of the following metals or alloys such as conventional titaniumalloys such as Ti6A14V, Ti5Al2.5Sn, or Ti-10V-Fe-3Al; stainless steelsuch as SAF2507; zinc alloys such as Zn5al, Zn10Al, Zn18Al, Zn30Al,platinum metal and its alloys; tin alloys such as Sn3.9Ag0.6Cu,Sn-3.8Ag-0.7Cu, SnPb, or SnPbAt; aluminum alloys such as A11.7Fe,A10.7Cu, A1.5MgScZr, Al6Mg0.2Sc0.15Zr, 3004, 8090, 7075, 6061, or 5056;zirconium alloy such as Zr55A110Ni5Cu30; magnesium alloy such as AZ31Bor MG11li5A11Zn0.034Sc (LAZ1151); iron alloy such as Fe29.7Mn8.7Al1C,30HGSA alloy steel, 4140, C45 steel, Fe36Ni, or low carbon steel; NickelAlloys such as Ni21Cr17Mo or Haynes 230; Tungsten or Tungsten alloys, orother. In a preferred example, the material strength after expansiondecreases by at least 25%, preferably by at least 50%, more preferablyby at least 75%, compared to the strength just after deployment (initialstrength), over a period ranging from 1 month to 3 years. The materialin a preferred example softens (decreased strength) comprising one ormore of the following reasons: body temperature, time, cycling (orfatigue), creep, recrystallization, grain growth, dislocation,precipitation interaction, dislocate interactions or other. The stentmaterial is degradable (including corrodible) or non-degradable. Thestent material can be formed as a tube and patterned into a stent,formed as a wire (or formed from a wire) and patterned into a stent, orformed as a patterned sheet (or formed from a patterned sheet) into astent.

In another example or aspect of this invention, a degradable stentprosthesis comprising degradable polymeric material or degradablemetallic or metallic alloy material, wherein the stent is configured tohave one or more separation regions, uncage after expansion (ordeployment), exhibit radial strain (or compliance) ranging from 1.5% to5%, further expands to a larger configuration after deployment(including after initial recoil), and/or expand in response to avaso-dilator. The stent is configured to have one or more of thefollowing: at least some rings (preferably substantially all rings) haveone or more of the following: gaps, bridging elements, separationregions, discontinuities. In a preferred example, the separation regionsare configured to form discontinuities before (or substantially before)the degradable stent degrades. In another example, the separationregions are configured to form discontinuities before the degradablestent degrades by a period ranging from 1 month to 5 years, preferablyby a period ranging from 2 months to 3 years, more preferably by aperiod ranging from 3 months to 1 year. In yet another example, theseparation regions are configured to form discontinuities within aperiod ranging from after initial expansion to 1 year after initialexpansion, preferably within a period ranging from one month afterinitial expansion to 9 months after initial expansion, more preferably,within a period ranging from one month after initial expansion to sixmonths after initial expansion.

In another example, the degradable stent material comprises metal ormetal alloy of Nickel, Cobalt, Tungsten, Iron, Zinc, Magnesium,Magnesium alloy AZ31, Tin, 1010 Steel, Steel, 5140 Steel, 8620 Steel,Iron Nickel Alloy, Cellulose, or other. In one example, the degradablematerial substantially degrades in a period ranging from 1 year to 20years, preferably degrades from 1 year to 10 years, more preferably in aperiod ranging from 1 year and 5 years, or most preferably in a periodranging from 6 months to 3 years. In one example, the degradable stentmaterial comprises (or composed of) polymeric stent material comprisesPLLA polymeric material. In yet another example, the degradable stentcomprises polymeric material comprising poly-lactide polymeric material.In yet another example, corrodible metal or metal alloy (degradable)that corrodes (degrade) from 1 to 10 years such as tungsten, tungstenalloys, Tungsten alloys of rhenium, cobalt, iron, zirconium, zinc,titanium; alloy of cobalt; magnesium alloy AZ31, tin, 1010 steel, steel,5140 steel, 8620 steel, iron nickel alloy; or the like. In yet anotherexample of Degradable polymer and copolymers that degrade from 3 to 10years examples include cellulose; chitin; chitosan; PLLA or itscopolymer; or the like.

In still further examples, the stents and other endoluminal prosthesesof the present invention may be formed from non-degradable metals ormetal alloys and/or other non-degradable materials and will beconfigured to have breaks, or openings formed (usually pre-formed) inthe scaffold circumferential structure (such as one or more rings) toallow uncaging of the stent after implantation in a vascular or otherbody lumen. The scaffold will typically be defined by a plurality ofcircumferential rings which are configured to expand from a crimpedcondition to an expanded configuration, where at least some of thecircumferential rings follow a circumferential path about thecircumference of the scaffold. There will be at least one break oropening in the circumference of at least some of the rings, and adjacentcircumference rings will be axially linked so that substantial portionsor segments of the scaffold remain connected and intact (by the axiallinks) after the scaffold has been expanded to its expandedconfiguration and the breaks (gaps) or discontinuities have formed inthe one or more rings. In some examples, the entire scaffold will remainboth axially and circumferentially connected so that no portion of thescaffold may inadvertently disconnect from the remainder of the scaffoldafter expansion and after the breaks (or discontinuities) have formed.In other examples, the expanded scaffold may separate into two, three,or more axially intact segments. In still other examples, the scaffoldmay separate into random segments after expansion, where such randomsegments will have sufficient size and persistence so they will notdislodge or substantially migrate from the implantation location inblood vessel or other body lumen after expansion. An example of that isa plurality of crowns and/or struts remaining connected within one ormore rings, and/or along the length of the scaffold.

In a first set of examples, the openings or breaks in the scaffold will(or may) comprise gaps in the circumferential rings. For example, thegaps may be formed in either or both of the struts and the crowns of thecircumferential rings. In some examples, the gaps will be closed whenthe scaffold is in its crimped (unexpanded) configuration and will openwhen the scaffold is expanded to its expanded configuration. Suchexamples include breaks in the struts or crowns where the adjacent edgesformed by the breaks remain in contact with each. Such “breaks” may beformed as part of the initials fabrication of the scaffold, e.g.patterning of a tube or bending of a wire, or may be formed after theinitial fabrication but cutting of severing a previously formed strut orcrown. In other examples, the gaps in the circumferential rings may bepresent even when the scaffold is in its unexpanded (crimped) conditionor the separation distance between the opposed ends of the gap and thestrut or crown will increase upon expansion of the scaffold. Suchinitially open gaps may also be formed during or after initialfabrication of the scaffold.

The gaps formed in the circumferential rings may be rotationallystaggered or rotationally aligned along a longitudinal or central axisof the scaffold. When the gaps in the circumferential rings arerotationally staggered, the adjacent rings may be joined by axiallylinks which are also formed in a staggered pattern which may be the sameor different than that of the rotationally staggered gaps. Similarly,when the gaps are rotationally aligned, the axially links may also berotationally aligned or rotationally staggered.

In a second set of examples, the openings or breaks in thecircumferential rings will (or may) comprise biodegradable segmentswhich form “bridges” between opposed surfaces or portions of the strutsor crowns which contain the break or opening. The biodegradable segmentsmay be configured to remain intact while the scaffold is expanded in avascular environment, forming gaps in the rings only after the bridgingsegments have degraded in the vascular or other luminal environment.Biodegradable segments may be configured to degrade in the vascular orother luminal environment over a time period in the range from 1 monthto 3 years, preferably degrade over a period ranging from 3 months toone year.

As with the gap embodiments described previously, the biodegradable“bridge” segments may be rotationally aligned or rotationally staggeredwithin the scaffold structure. Similarly, the axial links which holdadjacent circumferential rings together may also be rotationally alignedor staggered, and when staggered may be staggering in a pattern which issimilar to that of the staggered biodegradable segments.

For both the gap and the bridge examples, the scaffolds may display acomposite compliance (radial strain) in the range from 1% to 10%,usually from 1.5% to 5%, when expanded within a vascular environment (orunder physiologic conditions) and subjected to systolic/diastolicpressure cycling.

In yet another aspect of the present invention, in the vascularprostheses having a biodegradable bridging segment (element) in theirstruts and/or crowns may be made (or fabricated) as follows. A scaffoldis fabricated having a plurality of rings which define a circumferenceof the scaffold. The plurality of rings is (or maybe formed) formed froma non-degradable material, typically a metal. A second scaffold having aplurality of rings which define a circumference of the scaffold is alsofabricated but from a biodegradable material. Typically, the first andsecond scaffolds will (or may have) have identical geometries, at leastover the regions where the bridging structures are to be located. Afterthe first and second scaffolds are formed, gaps may be cut into at leastinto the struts and/or crowns of at least some of the rings of the firstnon-degradable scaffold. Corresponding segments are then cut from thesecond scaffold, where the segments are selected to fill in the gapsformed in the first scaffold. The segments cut from the second scaffoldare (or maybe) secured into the gaps formed in the first scaffold toform a complete scaffold having a non-degradable base structure with aplurality of degradable bridges in selected struts and/or crownsthereof.

In still further examples of the present invention, the scaffoldseparation regions of the present invention can (or maybe used) be usedin helical stents of the type having a helical backbone including aplurality of struts joined by a plurality of crowns. The helicalbackbone is formed to include a multiplicity of adjacent turns where atleast some of the adjacent turns are attached or otherwise coupled toeach other by a separation region. For example, the separation regionsmay be formed between immediately adjacent turns of the helicalbackbone, with specific examples including between adjacent pairs ofcrowns, between a crown on one turn and a strut on an adjacent turn, andbetween a pair of struts on adjacent turns. The helical backbonetypically has a serpentine arrangement, a zig-zag arrangement, orfollows another “meandering path” of the type commonly utilized in stentfabrication. The stents may be formed from a bent wire or alternativelymay be formed by patterning a tube in a conventional manner. Theseparation regions may comprise any one or more of the separationregions described elsewhere herein, such as degradable regions,mechanically separable regions, fatigue-responsive regions, bridgingelements, and the like.

In yet additional examples of the present invention, luminal prosthesesmay compromise scaffolds having a plurality of circumferential ringsformed from a non-degradable material, such as a metal, metal alloy, ora non-degradable polymer, where the scaffold is configured to expandfrom a crimped configuration to an expanded configuration. At least someof the circumferential rings will be formed from structural elements(such as crowns and/or struts) having divided regions which overlap andlie adjacent to each other when the scaffold is in its crimpedconfiguration. For example, the adjacent regions which overlap and lieadjacent to each other may be straight, typically together forming a“divided” portion of a strut of the scaffold, or may be curved,typically together forming a “dived” portion of a crown of the scaffold.Such straight adjacent regions will typically separate from each otherwhen the scaffold is expanded to its expanded configuration. Incontrast, such curved overlapping adjacent regions will typically deformwhen the scaffold is expanded to its expanded configuration, forexample, straightening in response to the bending forces applied byexpansion of the stent.

The overlapping adjacent regions may be initially unattached when thescaffold in its crimped configuration. Alternatively, the overlappingregions of the scaffold may be temporarily joined to each other, forexample, being held together by an adhesive, by an overlying sleeve, bya coating, and/or by any of the other permanent or temporaryimmobilization material, methods, and/or structures described hereinpreviously. Such temporary immobilization material (or structures),comprises degradable materials such as degradable polymeric material,will be configured to degrade in a physiologic environment, to fatigue,or to otherwise separate after implantation to enhance the compliance ofthe scaffold after the prosthesis has been implanted in a body lumen fora desired period of time. Permanent immobilization material comprisesnon-degradable material such as non-degradable polymeric material,wherein the material is typically elastic, allowing the stent prosthesisto have enhanced compliance after the prosthesis has been implanted in abody lumen for a desired period of time.

In still other examples, the scaffold separation technology (separationregions and other methods to uncage the circumferential strutcturalelements (or to allow for uncaging the stented segment of the lumen) asdescribed in various examples and/or aspects of this application) of thepresent invention may be applied to a variety of otherwise conventionalclosed-cell stent patterns. For example, the scaffold may have aplurality of circumferential rings formed from a non-degradable materialto expand from a crimped configuration to an expanded configuration. Atleast some of the circumferential rings will be formed as expandableclosed cell structures which are joined circumferentially, and suchcircumferential rings will have one or more separation regionsconfigured to form discontinuities in the rings after deployment in theluminal environment, uncaging the stented segment of the lumen. In somecases, at least two or more separation regions, in a circumferentialring, configured to form discontinuities, are necessary to uncage acircumferential ring, in other cases, at least three or more separationregions in a circumferential ring are required to uncage acircumferential ring. The one, two, three, or more separation regionsmay be located in the expandable closed cell structures and/or incircumferential connectors between the closed cell structures.

In specific examples, the closed cells may comprise quadrangles havingopposed axial sides and opposed circumferential sides. The scaffolds mayfurther comprise circumferential connectors which join the axial sidesof circumferentially adjacent closed cells, where the separation regionsmay be located in the circumferential connectors and/or in the closedcell structures themselves.

Typically, at least some of the closed cells in axially adjacentcircumferential rings will be joined by axial links, where the axiallinks are typically non-degradable and free from separation regions inorder to enhance the integrity of the stent after deployment, and/or inorder to enhance the stent uniformity of expansion, and/or in order tomaintain the structural integrity of the stent upon expansion, or afterexpansion.

The discontinuities which form in the scaffold after implantation willtypically allow the stent to display a compliance (or radial strain) andrange from 1% to 10%, preferably ranging from 1.5% to 5% once subjectedto systolic/diastolic pressure cycling (or vaso-dilator) afterimplantation, usually in a blood vessel of a mammalian.

In alternative closed cell configurations, the scaffolds may compriseclosely packed quadrangles formed from a plurality of common crossingmembers where the separation regions are present in the common crossingmembers and/or at junctions where the crossing members cross oneanother. The separation regions may comprise any of the separationregions described herein, often being biodegradable regions in theclosed cell scaffolds just described.

In still further examples of the present invention, a stent prosthesismay comprise a patterned circumferential scaffold includingnon-degradable structural elements. The structural elements may haveexpansion regions configured to plastically deform as the scaffold isradially expanded from a crimped configuration to a first expandedconfiguration. The structural elements (such as rings) may be furtherconfigured to allow the scaffold to passively (unaided by a mechanicalmeans and/or human intervention) expand to a second, largerconfiguration after experiencing (or exhibiting) inward recoil from thefirst expanded configuration after implantation. The scaffold willretain sufficient strength to support a body lumen for at least aninitial time period following implantation. The initial time period willtypically be at least about 1 day, often being at least 3 months, andtypically being in a range from 30 days to 9 months. The expansionregions may be any of the separation regions described previouslyherein. The second larger configuration may be larger than the firstexpanded configuration, or can be smaller than the first expandedconfiguration. In one example, the non-degradable structural elementscomprise a plurality of rings wherein each ring is composed of strutsand crowns, said non-degradable structural elements are composed ofmetal or metal alloy that plastically deforms when expanded from acrimped configuration to an expanded configuration. In one example, atleast some rings are configured to have one or more separation regions(in one or more struts and/or crowns of the at least some rings),wherein the separation regions are configured to form discontinuitiesafter expansion in physiologic environment.

In still further examples, the stent prosthesis of the present inventionmay comprise a non-degradable patterned, circumferential scaffoldincluding structural elements. The structural elements (such as rings)may have expansion regions configured to plastically deform as thescaffold is radially expanded from a crimped configuration to a firstexpanded configuration, and the scaffold may be further configured tohave a radial strain (or composite compliance) in a range from 1.1% to15%, preferably in a range from 1.2% to 10%, more preferably in a rangefrom 1.5% to 7% after the stent is expanded in a body and to retainsufficient strength to support the body lumen. These scaffolds are oftenfurther configured to have an inward recoil after deployment in a rangefrom 1.5% to 7%, and may further be configured to have an initial radialstrain (or compliance) after deployment of 1% or less before increasingto the radial strain in said range above. In additional examples, theradial strain of the stent prostheses just described may reach a valuein the desired range within two months to one year after deployment, anda diameter magnitude of the radial strain (or compliance) may be in arange of 0.07 mm to 0.5 mm, or of 0.1 mm to 0.5 mm In a preferredexample, at least some rings are configured to have one or moreseparation regions, wherein the separation regions are configured toform discontinuities after expansion of the stent under physiologicconditions. In another preferred example, all rings are configured tohave one or more separation regions, wherein the separation regions areconfigured to form discontinuities after expansion of the stent underphysiologic conditions. In yet another example, at least some rings havetwo or more separation regions, have three or more separation region,have one to four separation regions, or have 2 to 4 separation regions.

In other examples, stent prostheses according to the present inventionmay comprise a non-degradable, patterned circumferential scaffoldincluding structural elements, where the structural elements haveexpansion regions configured to plastically deform as the scaffold isradially expanded from a crimped configuration to a first expandedconfiguration. In some of these examples, the scaffold in the deployedconfiguration has a sufficient strength to support a body lumen, and thescaffold may be further configured (by incorporating one or more aspects(or examples) of the present invention as described throughout thisapplication, such as separation regions on at least some rings forexample) to allow a stented segment of the body lumen to vaso-dilate inthe presence of a vaso-dilator in the body lumen. The stented segment ofthe body lumen may vaso-dilate in the range of 0.05 mm to 0.5 mm andfrequently in a range from 0.1 mm to 0.3 mm, or in a range from 0.07 mmto 0.5 mm.

In yet additional examples of the stent prostheses of the presentinvention, a non-degradable, patterned circumferential scaffold mayinclude structural elements, where the structural elements haveexpansion regions configured to plastically deform as the scaffold isradially expanded from a crimped configuration to a first expandedconfiguration. The scaffold in the deployed configuration will havesufficient strength to support a body lumen, and the scaffold willtypically also be configured (by incorporating one or more of thevarious aspects (or examples) described in this application) to contractand/or expand after deployment in the body lumen under physiologicconditions. The expansion and/or contraction may occur passively oralternatively may occur in response to vaso-dilation and/orvaso-constriction of the body lumen. The expansion and/or contractionmay also occur under physiologic pulsation. Such expansion and/orcontraction often has a magnitude in a range from 0.05 mm to 1 mm, moretypically range from 0.1 mm to 0.5 mm relative to a deployed diameter ormean diameter of the body lumen.

In some examples, one or more of the following: at least one ring of thestent prosthesis, at least some rings of the stent prosthesis, all ringsof the stent prosthesis, at least some circumferential elements of thestent prosthesis, all circumferential elements of the stent prosthesis,and/or the stent prosthesis, of this invention is configured (byincorporating one or more of the present invention aspects (or examples)as described within this application) to do one or more of thefollowing: Un-caging of the lumen or vessel while having high crushresistance upon or after implantation of the stent, and/or uncaging thestented segment of the lumen or vessel, and/or a stent having sufficientstrength to support or hold the vessel or lumen open after implantationand further expands (after inward recoil if any) after implantation,and/or not having pieces of stents such as small components dislodginginto the blood stream potentially causing a clinical event, and/orhaving a stent with low inward recoil after initial expansion, and/orhaving a stent with low inward recoil after initial expansion that issubstantially maintained after implantation, and/or having a stent withlow inward recoil after initial expansion that increases by no more than1%-5% after said initial inward recoil, after implantation, and/orhaving a stent configured to be able to further expand (after inwardrecoil if any) after deployment under physiologic condition, and/orhaving a stent able to expand or further expand (after inward recoil ifany) after deployment without a pre-programmed temperature triggersetting or without a pre-programmed expanded diameter/configurationsetting, and/or having a stent able to expand or further expand (afterinward recoil if any) without a programmed temperature, and/or having astent able to further expand (after inward recoil if any) afterdeployment under physiologic condition without penetrating or withoutsubstantially penetrating the vessel or lumen wall, and/or having astent that does not cause excessive inflammation, and/or having a stentthat does not penetrate the lumen or vessel wall after implantation,and/or having a stents that expands further (after inward recoil if any)after deployment (implantation) further expanding the lumen or vessel,and/or having a stent maintained or substantially maintained in thecrimped configuration upon delivery into the vessel or lumen without aconstraint and further expand (after inward recoil if any) to a largerconfiguration after deployment, and/or having a stent that can bedeployed to a wide range of diameters and still uncages the vessel orlumen after deployment, and/or having a stent that can be deployed to awide range of diameters and still further expand (after inward recoil ifany) to a larger configuration after implantation, and/or having a stentable to further expand (after inward recoil if any) beyond thepre-programmed expanded diameter/configuration after implantation,and/or having a stent that exhibit vaso-motion, vaso-dilation, orvaso-constriction, after implantation, and/or having a stent that hassufficient strength after deployment to support a body lumen, has lowinward recoil (or said stent undergoes inward recoil) after the initialexpansion, and where the stent exhibits radial strain (or compliance)below 1% immediately after expansion (deployment), and a radial strain(or compliance) of 1% or larger than 1% after deployment, and/or havinga stent that has sufficient strength after deployment to support a bodylumen, said stent undergoes inward recoil after the initial expansion ofthe stent, and where the stent has an initial radial strain (orcompliance) after initial expansion, and wherein the radial strain (orcompliance) increases after deployment (or increases over time afterdeployment), and/or having a stent that has sufficient strength afterdeployment to support a body lumen, said stent undergoes inward recoilafter the initial expansion of the stent, and where the stent has aninitial radial strain (or compliance) after expansion (deployment), andwherein the radial strain (or compliance) increases, wherein theincrease in compliance ranges from 150% to 3000% the initial compliance,preferably wherein the increase in compliance ranges from 200% to 3000%the initial compliance, and more preferably, wherein the increase incompliance ranges from 300% to 3000% the initial compliance, and/orhaving a stent that has sufficient initial strength after deployment(initial expansion) to support a body lumen, said stent undergoes inwardrecoil after the initial expansion of the stent, and where the stent hasan initial radial strain (or compliance) after expansion (deployment),and wherein the radial strain (or compliance) increases after initialexpansion, preferably wherein the increase in compliance ranges from150% to 3000% the initial compliance, preferably wherein the increase incompliance ranges from 200% to 3000% the initial compliance, and morepreferably, wherein the increase in compliance ranges from 300% to 3000%the initial compliance, and wherein the initial strength decreases afterdeployment (or decreases after deployment over time, or preferablydecreases after deployment from 30 days to 1 year after deployment),and/or any of the above examples, wherein the stent does not undergo aninward recoil after initial expansion, and/or a stent as in any of theabove examples, wherein one or more of the stented segment furtherexpand by a magnitude ranging from 0.07 mm to 0.5 mm under physiologicconditions (including the infusion of vaso-dilator) into the vessel orlumen, and/or any of the examples under physiologic conditions, and/orhaving a stent that has sufficient initial strength after deployment(initial expansion) to support a body lumen (or annulus), and where thestent has an initial radial strain (or compliance) after expansion(deployment), and wherein the radial strain (or compliance) increases,after expansion, preferably wherein the increase in compliance rangesfrom 150% to 3000% the initial compliance, preferably wherein theincrease in compliance ranges from 200% to 3000% the initial compliance,and more preferably, wherein the increase in compliance ranges from 300%to 3000% the initial compliance, and wherein the stent prosthesis has aninitial configuration after an initial expansion of the stentprosthesis, and wherein the stent configuration changes afterimplantation (or after completion of the procedure), and/or any of theexamples under physiologic conditions, and/or having a stent that hassufficient initial strength after deployment (or after an initialexpansion) to support a body lumen (or annulus), and wherein the stentprosthesis has an initial diameter (or configuration (after an inwardrecoil if any), or wherein one or more segments of the stent has aninitial configuration) after an initial expansion (and after an inwardrecoil, if any) of the stent prosthesis, and wherein the stent diameter(or configuration, or one or more segments of the stent circumferentialelements (such as rings) changes after implantation (or after completionof the procedure, or changes over time, or changes over a period rangingfrom 30 days to one year, in one or more of the x-axis, y-axis, orz-axis of the stent, or one or more segments of the stent, and/or havinga stent that has sufficient initial strength after deployment (or afteran initial expansion) to support a body lumen (or annulus), and whereinthe stent prosthesis has an initial diameter after an inward recoil, ifany, (or configuration, or wherein one or more segments of the stent hasan initial configuration) after an initial expansion of the stentprosthesis and after an inward recoil, if any, and wherein the stentdiameter (or configuration, or one or more segments of the stentcircumferential elements (such as rings) becomes smaller or larger afterimplantation (or after completion of the procedure, or changes overtime, or changes over a period ranging from 30 days to one year, in oneor more of the x-axis, y-axis, or z-axis of the stent, or one or moresegments of the stent, to contour to the luminal (or annulus)configuration (or diameter) change.

In a preferred example, the stent prosthesis having (or may have) one ormore separation regions on at least some rings, preferably onsubstantially all rings, wherein the stent is expandable from a crimpedconfiguration to an expanded larger configuration and have sufficientstrength in the expanded configuration to support a body lumen, andwherein at least one separation region per at least some rings forms adiscontinuity in the circumferential path of said ring uncaging saidring, and wherein the stent after formation of discontinuities maintainsa structure pattern with the substantially the same number ofdiscontinuities as the number of separation region, wherein the numberof separation regions per ring ranges from 1 to 4.

In a preferred example, the stent prosthesis having (or may have) one ormore separation regions on at least some rings, preferably onsubstantially all rings, wherein the stent is expandable from a crimpedconfiguration to an expanded larger configuration and have sufficientstrength in the expanded configuration to support a body lumen, andwherein at least one or more separation regions per at least some ringssufficient to form at least one discontinuity in the circumferentialpath of said ring uncaging said ring, and wherein the stent afterformation of discontinuities maintains a structure pattern with thesubstantially the same number of discontinuities as the number ofseparation region, wherein the number of separation regions per ringranges from 1 to 4.

In one example, the stent in accordance of this invention is configuredto uncage upon expansion or after expansion from a crimped configurationto an expanded larger configuration and have sufficient strength tosupport a body lumen or annulus in the expanded configuration. At leastsome rings, or at least some stent segments, or at least some stentregions, or substantially all rings, ring segments, or ring regions, orthe stent, uncage after expansion. Uncaging comprises one or more of thefollowing: having one or more breaks, discontinuities, separations, in acircumferential path of each of the at least some rings, or of each ofthe at least some circumferential structural elements, or of the stentcircumferential elements, sufficiently to separating the rings,circumferential structural elements, and/or the stent in at least one ormore circumferential direction; having the stent or a stent segmentbeing able to expand to a larger configuration after expansion and afterformation of discontinuities, having a stent or a stent segment in theexpanded configuration exhibiting radial strain (or compliance) rangingfrom 1% to 10%, preferably ranging from 1.5% to 7%, more preferably from2% to 5%; having a stent or a stent segment in the expandedconfiguration (after expansion) exhibiting contraction or expansion,expansion and contraction, expansion and/or contraction ranging from 0.1mm to 1 mm, preferably ranging from 0.15 mm to 0.7 mm, more preferablyranging from 0.2 mm to 0.5 mm, and/or having a stent in the expandedconfiguration being responsive to vaso-dilators and/orvaso-constrictors, and/or other therapeutic agents; or other.

In some examples, a non-degradable stent material is preferred for itshigh strength (or high crush resistance) properties or other mechanicalproperties. A degradable material such as metallic or metallic alloy canbe configured to have high crush resistance and properties substantiallysimilar to non-degradable material or to non-degradable alloy andtherefore can also be suitable for these examples or embodiments. Insome examples, the biodegradable material can be configured to havesufficient strength in the stent expanded configuration to support abody lumen and degrade in a period ranging from 3 months to 10 years,preferably degrade in a period ranging from 1 year to 5 years. Adegradable material can also be polymeric material having sufficientstrength in the expanded configuration and degrades over a time periodranging from 3 months to 10 years, preferably degrading in a periodranging from 1 year to 5 years.

In one example, a coronary stent comprising 2.0 mm to 4.0 mm diameterexpansion range by one or in some cases multiple stents to accommodatesuch range, 15 mm to 40 mm stent length range, formed from a wire, atube, or a sheet rolled up into a tube (patterned before or afterrolling into a tube), having strut thickness ranging from 50 microns to150 microns, preferably thickness ranging from 50 microns to 120microns.

In a preferred example, a stent configured to uncage after expansion inaccordance with one or more aspects of this invention, is desired tohave the ability to withstand fatigue for at least 400M cycles, or tohave stresses and/or strains on structural elements such as rings,expansion regions (such as crowns), non-deformable regions (such asstruts), or axial links connecting adjacent rings, to be sufficiently ina range to withstand 400M cycles of stent fatigue without uncontrolledfracture. In one example, the expansion region of the stent isconfigured to uncage, can have a wider neck, a key hole type design, orother design, shape, geometry to maintain stresses or to distributestresses along a longer or larger area, when one or more separationregions on the same ring or adjacent ring form discontinuities. Otherexamples include larger width or thickness of structural elements,longer structural elements, and/or varying the number, location, shapes,and geometry of separation regions. Another example is manipulating theaxial links locations, shape, and number. In another example, having oneor more rings with one or more separation regions followed by one ormore adjacent rings that do not have separation regions or a differentnumber of separation region on said rings to manage overall stresses onthe stent structure and on the rings with separation regions. In apreferred example, the stent of this invention is configured afterexpansion to have support to the body lumen or annulus withoutsubstantial incremental stresses to the body lumen or annulus, while thestent remain axially connected.

In another example of any of the examples in this application, at leastone ring having one or more separation regions and/or joints, and/or thestent prosthesis is desired to withstand an approximately 400 millioncycles simulating approximately 10 years of heart beats. The stent isconfigured to have a safety factor of one, preferably greater than one,more preferably greater than 1.2 safety factor on the Goodman line. TheGoodman line in one example is generated as follows: In a graph ofAlternating stress measured in MPa of the stent material, versus meanstress measured in MPa also of the stent material, the mean andalternating stress for every point in the stent subject to physiologicalconditions (for example using FEA or physical testing to generate suchpoints simulating physiological conditions) is desired to fall on orbelow a line connecting the fatigue limit measured in MPa (measured fromthe stent material sample) on the alternating stress axis, and theultimate stress on the mean stress axis (that is the Goodman line),giving a factor of safety of one, greater than one, or preferable 1.2 orgreater factor of safety. This allows simulating approximately ten yearfatigue cycle of the stent prosthesis under physiologic conditionwithout breakage. In another example, the stent prosthesis is configuredto have controlled breakage or discontinuities at certain location onone or more circumferential structural element (such as rings), and atapproximate time duration within ten years, or beyond.

In one example, a non-degradable stent prosthesis comprising anon-degradable metal alloy such as L605 that is patterned from a tube ora wire, wherein the stent is configured in accordance with one or moreaspects or examples of this invention to uncage after expansion in abody lumen or under physiological conditions, said stent has sufficientstrength in the expanded configuration to support a body lumen, andwherein the stent strength after expansion decreases. The stent furthercomprises a degradable coating and a drug agent (incorporated in thecoating or separate from the coating) to suppress neointimalproliferation. In one example the stent strength decreases from thedeployed strength (after deployment immediately or within 1 hour) by arange from 25% to 75% over a period ranging from 1 month to 1 year afterdeployment. In another example, the stent strength decreases from thedeployed configuration strength by a range from 50% to 90% over a periodranging from 1 month to 1 year after deployment. In yet another example,the stent strength decreases to zero after deployment in a periodranging from 1 month to 2 years.

In one example, a stent prosthesis comprising a non-degradable metalalloy such as L605 that is patterned from a tube or a wire, wherein thestent is configured to uncage after expansion in a body lumen (or underphysiological conditions), said stent has sufficient strength in theexpanded configuration to support a body lumen, and wherein the stentstrength after expansion is substantially maintained. The stentoptionally further comprises a degradable coating and/or a drug agent tosuppress neointimal proliferation. In one example the stent strengthdecreases from the deployed strength (after deployment immediately orwithin 1 hour) by a range from 25% to 75% over a period ranging from 1month to 1 year after deployment. In another example, the stent strengthdecreases to a level still sufficient to support a body lumen. Inanother example, the stent strength decreases to a level insufficient tosupport a body lumen in the absence of neointimal proliferationmaintaining the uncaged stent substantially in place.

In another example, a stent prosthesis comprising a degradable metallicmaterial, such as Tungsten or Tungsten alloy, wherein the stentprosthesis is configured to uncage (by incorporating on eor more exampleor aspects of this invention such as one or more separation regions)after expansion in a body lumen and wherein the stent prosthesis in theexpanded configuration has sufficient strength to support a body lumen,and wherein the metallic material degrades in a period ranging from 1year to 5 years. The stent optionally further comprises a degradablecoating and/or a drug agent to suppress neointimal proliferation. In anexample where separation region provide discontinuities providing foruncaging of the stent, the discontinuities are usually configured toform before the degradation of the degradable metal or metal alloy.

In another example, the stent prosthesis as in any of the examples oraspects of this application, comprises circumferential structuralelements patterned to expand from a crimped configuration to an expandedlarger configuration, and wherein the stent in the expandedconfiguration has sufficient strength to support a body lumen andwherein the stent is configured to circumferentially uncage (formingdiscontinuities in at least some rings or all rings) after expansionunder physiologic conditions. The stent in one example comprises aplurality of rings connected by one or more axial links, wherein atleast one or more links are configured to separate at about the sametime as the stent uncages circumferentially, or separate after the stentuncages circumferentially, or separate before the stent uncages, or acombination thereof, while at least one link remains intact between twoadjacent rings, or while at least one link remains intact between alladjacent rings, or while at least some adjacent rings remain joined inone region.

In another example of any of the examples in this application, the stentprosthesis is configured to have one or more of separation regions,gaps, bridging elements, and/or discontinuities, etc., wherein thestructural elements adjacent to said separation regions, gaps, bridgingelements, and/or discontinuities, are configured (or allowed) to move ina circumferential direction, and/or configured (or allowed) to move in alongitudinal direction, and/or configured (or allowed) to move in aradial direction, and/or allow movement in a combination of the above.

In another example of any of the examples in this application, the stentprosthesis is configured to have one or more of separation regions,gaps, and/or discontinuities, etc., wherein the structural elementopposite ends adjacent to said separation regions, gaps, and/ordiscontinuities, are configured to do one or more of the following: movefreely in relationship to one another, move in a confined direction (ormanner), move in an unconfined direction (or manner), move in aconstrained fashion (or manner), move in an unconstrained fashion (ormanner), wherein such movement is longitudinal, radial, circumferential,or combination thereof.

In another example of any of the examples in this application, the stentprosthesis in the expanded configuration comprising structural elementswherein at least some of the structural elements are configure to allowmovement of the at least some circumferential elements in one or moredirections (such as circumferential, longitudinal, radial, orcombination thereof) wherein said movement uncages at least saidstructural elements, further expands said at least some structuralelements, allow vaso-dilation of the at least some structural elements,allows the at least some structural elements to contract and/or expand,under physiologic conditions. In another example the stent prosthesiscomprising structural elements (crowns and/or struts) wherein at leastsome of the structural elements are configured to have one or more ofseparation regions, joints, gaps, bridging elements, junctions, whereinthe separation regions, gaps, bridging elements, joints, junctions, formdiscontinuities after expansion of the stent prosthesis, wherein saiddiscontinuities uncages the at least said structural elements, furtherexpands said at least some structural elements, allow vaso-dilation ofthe at least some structural elements, allows the at least somestructural elements to contract and/or expand, under physiologicconditions. In another example the stent prosthesis comprisingstructural elements (crowns and/or struts) wherein at least some of thestructural elements are configured to have one or more of separationregions, joints, junctions, gaps, bridging elements, wherein the one ormore of separation regions, gaps, bridging elements, joints, junctions,allow the said structural elements to move, after expansion of the stentprosthesis, in one or more directions (such as radial, circumferential,and/or radial), and wherein said movement uncages the at least saidstructural elements, further expands said the at least some structuralelements, allow vaso-dilation of the at least some structural elements,allows the at least some structural elements to contract and/or expand,under physiologic conditions.

In another example of any of the examples in this application, the stentprosthesis comprising structural elements (crowns and/or struts) whereinat least some of the structural elements are configured to uncage afterexpansion of the stent prosthesis from a crimped configuration to anexpanded larger configuration, and wherein the uncaging of the stentcomprises allowing the at least some structural elements to move in oneor more directions (comprising one or more directions ofcircumferential, radial, or combination thereof), and wherein saidmovement allows the at least some structural elements (or the stent) tofurther expands, to exhibit vaso-dilation, to contract and/or expand, tohave higher radial strain (be more compliant), under physiologicconditions.

In one example the stent prosthesis comprising structural elementsformed from a metallic or polymeric material, and wherein the structuralelements forms the stent pattern, and wherein the stent patterncomprises open cell type design, closed cell type design, helical stenttype design, coil stent type design, braided stent type design, and/orcombination thereof, and wherein at least one segment of the stentand/or the stent prosthesis is configured to uncage in accordance withthis invention (comprising one or more of separation regions, gaps,reinforcement elements, junctions, joints, discontinuities, etc.,) in atleast one segment (preferably the entire stent segment) in the expandedstent configuration, allowing the at least one segment and/or the stentto move in one or more directions comprising a circumferentialdirection, a radial direction, a longitudinal direction, and/orcombination thereof, where such movement allows the at least one segmentand/or the stent to have one or more of the following: increased radialcompliance (radial strain), contraction and/or expansion from theexpanded configuration, further expansion after recoil (if any),exhibiting or responding to a vaso-dilator, under physiologicconditions, wherein the movement is substantially higher after uncagingof the at least one stent segment and/or the stent.

In one example the stent prosthesis comprising structural elementswherein the structural elements comprises a plurality of rings whereinat least some rings comprises struts joined by crowns, and wherein atleast some rings are connected to adjacent rings at one or more surfaceregions, and wherein the at least some rings have one or more separationregions, discontinuities, junctions, gaps, joints, bridging elements,reinforcement elements, and wherein the stent prosthesis beingexpandable from a crimped configuration to an expanded largerconfiguration, and wherein the at least some rings and/or the stentuncages after deployment to the expanded configuration, and wherein theat least some rings and/or the stent exhibit one or more of thefollowing after uncaging compared to before uncaging in the expandedstent configuration: increased radial strain (radial compliance),increased vaso-dilatation or vaso-constriction, further expand to asecond expanded configuration (after inward recoil if any from thedeployed configuration), increased contraction and/or expansion afterdeployment, under physiological conditions.

In another example, the stent prosthesis as in any of the examples inthis application, wherein the stent being expandable from a crimpedconfiguration to an expanded larger configuration (first expandedconfiguration or initial expansion) and have sufficient strength in theexpanded configuration sufficient to support a body lumen, and whereinthe stent is configured in accordance with one or more aspects of thisinvention to uncage after expansion allowing for one or more of thefollowing: increased radial strain, further expand to a second expandedconfiguration after inward recoil from first expanded configuration,increased radial contraction and/or expansion, increased radial orcircumferential displacement, than before uncaging, under physiologicconditions.

In another example, the stent prosthesis as in any of the examples inthis application, wherein the stent being expandable from a crimpedconfiguration to an expanded larger configuration (first expandedconfiguration) and have sufficient strength in the expandedconfiguration sufficient to support a body lumen, and wherein the stentis configured to have (or to allow) movement of at least some of thestent structural elements and/or the stent in one or more directions(such as circumferential, radial, longitudinal, and/or combinationthereof) after expansion allowing for (or resulting in) one or more ofthe following: higher radial strain, further expansion to a secondexpanded configuration after inward recoil from first expandedconfiguration, higher radial contraction and/or expansion, higherradial, or circumferential displacement, than before allowing saidmovement of the at least some structural elements and/or the stent,under physiologic conditions.

In another example, the stent prosthesis comprising structural elements,wherein said structural elements comprise a stent pattern, and whereinthe stent being expandable from a crimped configuration to an expandedlarger configuration and have sufficient strength to support a bodylumen, and wherein the stent is configured to uncage and to havemovement (in one or more directions) in the expanded configuration,larger than the movement in the caged configuration, under physiologicalconditions. In another example of this example, the stent strength afterexpansion is substantially maintained until at least some of the stentstructural elements are covered with biological tissue (or material, orcells). In another example of this example, the stent strength afterexpansion is substantially maintained until at least substantially allof the stent structural elements are covered with biological material(or tissue, or cells). In another example of this example, the stentstrength after expansion is substantially maintained until at least someof the stent structural elements are covered with biological material(or tissue, or cells), and wherein the stent is configured to uncage insome regions along the stent as described in various aspects or examplesin this application, and wherein the biological material substantiallyholds the uncaged patterned stent in place.

In another example, the stent prosthesis as in any of the examples ofthis application, wherein the stent is configured to have a movement inone or more directions in at least one segment of the stent prosthesis,wherein the movement comprises displacement in said one or moredirections, under physiologic conditions. In another example of thisexample, the one or more direction comprises circumferential, radial,and/or longitudinal, combination thereof, and/or other directions, orother directions patterns. In another example of this example, the stentprosthesis comprises uncaging of the at least one segment allowing saidmovement (or displacement), and wherein the movement (or displacement)in one or more direction is larger than said movement (or displacement)before uncaging, under physiologic conditions.

In another example, the stent prosthesis can have a variety of shapes,forms, and structures. For example, structural elements can comprisestruts or screw like elements, crowns or knots or bolts type joiningstruts and/or screw type elements together. The examples of thisapplication apply to the various types of stents, prosthesis, and otherimplants such as vascular or non vascular stents, stents containingvalves, and/or other prosthesis or implants, where one or more of thefollowing is desired: uncaging of the stented segment lumen or part ofthe stented segment lumen, increased radial compliance from an initialcompliance, high initial strength that decreases after implantation (orover time), provide for one or more stent segments (or the stentedsegment) to further enlarge after implantation, provide for having oneor more stent segments (or the stent) having an initial configuration(shape, and/or diameter) substantially contouring to a vessel, lumen, orannulus, upon expansion, to continue to contour (or to continue tosubstantially contour) to the vessel, lumen, or annulus, afterimplantation, in response to a change in the vessel, lumen, or annulusconfiguration, under physiologic conditions, and/or a desireddisplacement after implantation is required in one or more diameterdimensions of one or more stent segment (or the stent).

In another example, the various examples and aspects of this inventionapplies to not only expandable prosthesis, but applies to a variety ofimplants such as non-expandable implants where they are attached orplaced in a body lumen (or placed adjacent to a body lumen or annulus,or placed in tissue) and wherein such implants are configured to provideuncaging, and/or provide desired displacement (in diameter for example)after implantation in at least one segment or region of the implant.

In one example, an implant having length, width, and thickness, isattached (or held in place) adjacent to a body lumen or a body annulusand wherein the implant is configured to be coupled with (or attached)to an expandable prosthesis, and wherein at least one of the implant andthe stent prosthesis are configured to have one or more of separationregions, junctions, joints, hinges, bridging elements, gaps, on at leastone segment or region of the implant and/or stent allowing the at leastone segment or region of implant and/or stent to have displacement(change in diameter), in one or more direction or one or more axis (x,y, or z), that is larger than an adjacent segment (or region) of thesaid implant or stent prosthesis.

In yet another example or aspect of the present invention, a stentprosthesis comprises a scaffold having circumferential rings patternedfrom a polymeric or metallic material. The scaffold is configured toexpand from a crimped configuration to an expanded configuration, and atleast some of the circumferential rings have at least onecircumferential displacement region which allows the circumferentialring to circumferentially expand and contract in a physiologic luminalenvironment, such as a blood vessel, and more particularly an arterialblood vessel. For example, the displacement regions may allow the one ormore circumferential rings to circumferentially expand and contract inresponse to a patient's systolic/diastolic rhythm in an arterial lumen.

The displacement regions in one example will allow such circumferentialexpansion and contraction after implantation of the stent prosthesis inthe blood vessel or other body lumen. While the displacement regioncould be any of the separation regions, open gap, or key-and-lockstructures, or others, described previously, they will frequently beregions which are joined or filled by a material (including polymericmaterial) such as an elastomeric cushion material, such as anelastomeric polymer. In such cases, the elastomeric cushion materialwill frequently join or connect adjacent regions on the circumferentialrings, thus acting as an elastic restraint which permits relativemovement of adjacent segments and/or regions to accommodate pulsing ofthe blood vessel or other body lumen, or other physiologic condition.The amount or degree of relative movement between immediately adjacentstent regions may vary widely, often being in the range from 0.01 mm to1 mm, often from 0.03 mm to 0.5 mm, and frequently from 0.05 mm to 0.5mm. The amount or degree of stent circumferential elasticity may alsovary widely, often being in the range from 0.05 mm to 0.2 mm, often from0.07 mm to 0.15 mm, and frequently from 0.07 mm to 0.012 mm.

The scaffolds having circumferential displacement regions in accordancewith the principles of the present invention in one example willtypically include a plurality of circumferential rings coupled togetheralong an axis. In such instances, at least some of the circumferentialrings will often comprise struts joined by crowns, where at least someof the struts or crowns will have circumferential displacement regionsthat allow the circumferential ring(s) to circumferentially expand andcontract in response to the systolic/diastolic rhythm in an arteriallumen, and/or other physiologic conditions. Such regions may comprisediscontinuities such as gaps, channels, breaks, junctions, bridgingelements, and the like, between adjacent or opposed segments of a strutor crown. In specific examples, the gaps may be defined by opposedsegments of a strut and comprise a female coupling element, typicallyhaving a pair of opposed constraining walls attached at one end of thestrut segment, and a male coupling element disposed on an opposed strutsegment. By locating the male strut segment between the pair of opposedconstraining walls on the adjacent strut segment, the male element andfemale element will be free to at least circumferentially move relativeto each other to provide the desired circumferential expansion andcontraction.

As described previously in other examples, the gaps may be left open orin other instances may be filled with an elastomeric cushion materialwhich dampens the circumferential movement of the male element betweenthe opposed walls of the circumferential rings. Depending on the size ofthe gap, the male element will be able to move axially, laterally,and/or in elevation relative to the adjacent strut segment. Such abilityto move with multiple ° of freedom enhances the elasticity of the stentin response to body lumen pulsation. In other examples, the gap betweentwo opposed segments of a strut may comprise a coupling element having achannel that includes a pair of opposed constraining walls and a bottomsurface. A male coupling element opposed on an adjacent strut segmentwill be located within the channel defined by the opposed constrainingwalls and bottom surface, allowing the male element to move at leastcircumferentially between the opposed walls and axially within thechannel. As with previous examples or embodiments, the channel may beleft open or may be filled with an elastic material or other material(including polymeric).

In yet another example of a circumferential displacement region inaccordance with the principles of the present invention, gaps may bedefined between opposed segments of the strut and further comprise acoupling element there between. For example, a pin may be positioned tospan a gap between a pair of opposed walls of a female coupling elementand to further pass through a pivot hole and a male coupling elementthere between, allowing for movement, and/or for expansion andsubstantially maintaining said expansion, and/or for expansion andcontraction. In still another example or aspect of the presentinvention, a method for fabricating a stent prosthesis comprisespatterning two or more panels or sheets of stent material to include aplurality of partial ring structures. Each partial ring structure willbe formed to terminate in two or more attachment ends so that the two ormore panel structures, which are typically initially flat, may be formedinto a cylindrical assembly with each attachment and on one panel beingjoined to an adjacent attachment structure on another panel. Afterproperly positioning the adjacent panel structures, the attachment endswill be joined to complete the circumferential stent structure.

The partial ring structures in one example will typically comprisestruts joined by crowns and the attachment ends will often be patternedas male and female elements configured to mate with a gap there between,where the gap allows the circumferential scaffold to circumferentiallyexpand and/or contract in the physiologic luminal environment.Optionally, the gaps may be left open but more often will be filled witha material, preferably a polymeric material, more preferably with anelastomeric material to provide an elastic attachment between theattachment ends. The material can be degradable or non-degradable.

Forming the two or more panel structures into a cylindrical assembly inone example typically comprises bending the panels over a mandrel,usually a cylindrical mandrel. After the two or more panels are formedinto their desired shapes, the adjacent end structures on each panel maybe joined, typically by applying an elastomeric material between or overthe adjacent end structures.

In still another example or aspect of the present invention, a stentprosthesis comprises a scaffold having circumferential rings patternedfrom a polymeric or metallic material (including non-degradable anddegradable). The scaffold is configured to expand from a crimpedconfiguration to an expanded configuration, and at least some of thecircumferential rings are joined by axial links where at least some ofthe axial links are joined to an adjacent circumferential ring by acircumferential displacement region. The circumferential displacementregion(s) allow the circumferential ring to circumferentially expandand/or contract in a physiologic environment, while maintaining theaxial link(s) intact (connecting two adjacent rings) in a preferredexample.

In certain examples, at least one displacement region wherein thedisplacement is in at least one direction, such as circumferentialdisplacement region allows the circumferential ring to circumferentiallyexpand and/or contract in response to a systolic/diastolic rhythm in anarterial lumen, or other physiologic conditions. Usually, the scaffoldincludes a plurality of circumferential rings coupled together along anaxis by axial links. In such instances, at least some of thecircumferential rings typically comprise struts joined by crowns, and astrut on the adjacent circumferential ring terminates in thecircumferential displacement region which is joined to the axial link.

As with previous examples, the displacement regions wherein thedisplacement is in at least one direction, such as circumferentialdisplacement regions may comprise discontinuities which allow thecircumferential ring(s) to at least circumferentially expand and/orcontract in response to a systolic/diastolic rhythm in an arteriallumen, typically comprising gaps between opposed segments of a strut ora crown. More typically, the circumferential displacement regionscomprise a male segment and a female coupling element. Where the malesegment will typically be at a terminal end of a strut and the femalecoupling element is on the axial link. Conversely, the female segmentmay be at a terminal end of a strut and the male coupling element belocated on an axial link.

In one example of any of the examples of this application, the implantcomprises a stent, a substantially tubular stent in the crimpedconfiguration, a substantially tubular stent in the expanded (deployed)configuration, a tubular stent in the expanded and/or crimpedconfiguration, a cylindrical or substantially cylindrical stent in thecrimped and/or expanded configuration, a non-cylindrical stent in thecrimped and/or expanded configuration; wherein the stent is expandablefrom a crimped configuration to an expanded larger configuration and hassufficient strength to support a body lumen (including annulus).

In another example of any of the examples of this application, theimplant is a fixation device to anchor to a body lumen, adjacent to abody lumen (including annulus), or anchor to an anatomy; where thefixation device connects to another implant (such as stent, a valve(native or synthetic).

In another example of any of the examples of this application, theimplant (prosthesis) is an arterial stent, a stent for valve repair orreplacement, a fixation device for valve repair or replacement, and/or aluminal stent.

In another example of any of the examples of this application, theimplant comprises a stent wherein the stent is expandable from a crimpedconfiguration to an expanded larger configuration and has sufficientinitial strength in the expanded configuration to support a body lumen(or annulus), and has one or more of the following: an initial shape, aninitial displacement, an initial radial strain, an initial vaso-motionreactivity; and wherein the stent prosthesis after expansion will haveone or more of the following: increased radial strain, increased radialstrain and decreased strength from the initial strength, decreasedstrength below the initial strength, increased displacement in at leastone direction wherein the initial displacement in said direction issubstantially small, having displacement in at least one direction wherethe initial displacement is substantially zero in said at least onedirection, and/or changes the shape of the stent from the initial shapeafter expansion. The stent in the above example is configured to haveone or more of the following: Uncaging, having variable compliance(radial strain) after expansion, having controlled compliance (radialstrain) after expansion that is different from the radial complianceupon expansion, having adaptive to lumen or vessel compliance (radialstrain) after expansion, having variable displacement, having controlleddisplacement different from initial expanded configuration, havingadaptive to lumen or vessel displacement after expansion or deployment,having variable movement, having controlled movement, having adaptive tolumen or vessel movement after expansion, and/or allowingvaso-reactivity after expansion. The stent in this example includesstents that are degradable and stents that are non-degradable stents,metal stents, polymer stents, or combination. The implants include butare not limited to stents, tubular structures, non-tubular structures,and other implants having a structure in the expanded and/or crimpedconfiguration. In another example the stent prosthesis has asubstantially cylindrical shape upon deployment (expansion) from acrimped configuration to an expanded configuration, wherein the stentshape changes after expansion to one of: non cylindrical, substantiallynon cylindrical, oblong, oval, or other shape; to accommodate changes ina body lumen (including annulus).

In another example of any of the examples of this application, the stentprosthesis after expansion has an initial shape (or shape configuration)that substantially fits or suited to a body lumen (including annulusshape), and wherein the said shape (or shape configuration) of the stentafter expansion changes to accommodate a change in the body lumen(including annulus shape changes) shape (or shape configuration);preventing or minimizing said fit mismatch, or having improved fitcompared to an initial fit before said change of lumen shape orconfiguration after initial expansion of the stent. In another example,the change in shape (or shape configuration) after expansion isdynamically changing shape (or shape configuration) corresponding to theforces exerted by the lumen, while substantially maintaining theexpanded configuration of the stent.

In one example of any of the examples of this application, the implantis a fixation device having initial shape, displacement, and fixationstrength, and wherein the implant after fixation adjacent to a bodylumen or within a body lumen has one or more of the following: largerdisplacement in at least one direction, changes the shape in at leastone dimension, decreases strength in at least part of the implant, orother.

In another example, the stent prosthesis configured to have separationregion or joints further expand to a second larger configuration underphysiologic environment, wherein the stent would not further expand ifnot exposed to physiologic conditions. In another example, the stentprosthesis as in any of the examples of this application further expandsto a second larger configuration (after initial inward recoil if any)only under physiologic conditions.

In another example, the stent prosthesis exhibit vaso-reactivity afterdeployment, and prior to formation of discontinuities, and/or exhibitvaso-reactivity over substantially the entire stented segment.

In one example of any of the examples of this application, the stentcomprises one or more separation regions (or discontinuities), whereinthe separation regions (or discontinuities) comprises one or morejoints, wherein the joints allows movement or displacement in at leastone direction or dimension after expansion, and wherein the joints donot come apart in physiological conditions.

In one example of any of the examples of this application, the stentcomprises one or more separation regions (or discontinuities), whereinthe separation regions (or discontinuities) comprises one or morejoints, wherein the joints allow movement or displacement in at leastone direction or dimension after expansion, and wherein the joints comeapart after expansion in physiological conditions.

In one example of any of the examples of this application, wherein thestent comprises a plurality of rings and wherein at least some ringshave one or more separation regions (or joints), configured to formdiscontinuities (or displacement) at substantially the same, ordifferent time periods.

In one example of any of the examples of this application, the implant(including stents) has one or more separation regions wherein theseparation regions comprise joints, wherein the joints allowdisplacement in at least one direction after expansion. Example ofjoints include but are not limited to: pivot type joint, hinge typejoint, ratchet type joints, saddle type joint, ball-and-socket typejoint, condyloid type joint, and/or plant type joint. In one example thejoint do not come apart. In another example the joints come apart, afterexpansion. In another example, the implant has an initial displacementupon expansion that is less than the displacement magnitude afterexpansion.

In one example, the separation region comprises a joint. In anotherexample, the separation region is a joint.

In one example of any of the examples of this application, the implant(including stent) has an initial shape upon expansion, and one or moreseparation regions wherein the separation regions comprise joints,wherein the joints allow change in said shape after expansion. Exampleof joints include but are not limited to: pivot type joint, hinge typejoint, ratchet type joint, saddle type joint, ball-and-socket typejoint, condyloid type joint, and plant type joint. In one example thejoint do not come apart. In another example the joints come apart, afterexpansion.

In one example of any of the examples of this application, the stentprosthesis comprises a plurality of circumferential rings, wherein atleast one ring has one or more separation regions (or joints) formingdiscontinuities (or displacement(s)) after expansion in physiologicconditions.

In another example of any of the examples of this application, thephysiologic conditions comprise one or more of: body lumen (includingannulus), physiologic pressure, heart beat, muscle contraction,temperature of about 37 C, temperature of about 37 C where the implantis in a water bath at said temperature, a sleeve mimicking a body lumen(or annulus), and/or a test fixture mimicking physiologic conditions.

In one example of any of the examples in this application, the stentprosthesis comprises at least one ring, wherein the ring comprisesstruts joined by crown, and wherein the rings comprise one or moreseparation regions, or one or more joints along the circumferential pathof said ring, configured to form discontinuities, and/or displacement,and/or change in shape configuration. In one example, the one or moreseparation regions or joints are located on struts and/or crown regions,allowing at least the ring to uncage, to have displacement, to furtherexpand and/or contract, and/or change shape configuration, afterexpansion of the stent prosthesis in physiologic environment.

In one example of any of the examples of this application, wherein thestent prosthesis comprise one or more separation regions (ordiscontinuities) and wherein said separation region or discontinuitiesafter expansion has one or more of the following: displacement in one ormore directions, increased displacement in one or more directions,change in shape configuration from initial expanded shape configuration,change in radial strain from initial expanded radial strain, increasedradial strain from initial expanded radial strain, decreased strength,decreased strength from initial expanded strength, increased radialstrain while decreased strength from initial radial strain and initialstrength.

In one example, the stent prosthesis or implant comprises one or moreseparation regions wherein the separation regions comprise linkages.Linkages allow for displacement (movement) in the same direction (PushPull Linkages) or in opposite directions (Reverse Motion Linkages).Linkages may be connected in a variety of ways including pins, screws,split pins, polymer fasteners, pop rivets, clevis pins, and/or nut andbolts, etc. The linkages may change the magnitude or direction of thedisplacement, increase displacement magnitude, reverse displacementdirection or magnitude, or combination thereof.

In one example, the stent prosthesis or implant comprises one or morejoints wherein the joints are connected in a variety of ways includingpins, screws, split pins, polymer fasteners, pop rivets, clevis pins,and/or nut and bolts, etc.

In one example of any of the examples of this application, theprosthesis is an implant comprising one of: stent, implant having astructure, implant having a structure, implant having a structure and afixation means, or other.

In one example of any of the examples of this application, the stentprosthesis comprising a plurality of adjacent rings, whereinsubstantially all rings comprise one or more separation regions,discontinuities, or joints, and wherein substantially all rings arecapable of one or more of the following: similar radial strain (orcompliance) magnitude or change, vaso-motion reactivity of substantiallyall rings that is substantially similar, uncaging of substantially allrings, further expansion to a larger configuration of substantially allrings, expansion and/or contraction of substantially all rings,displacement in at least one direction (or dimension), change in shapeconfiguration, after expansion from a crimped configuration to anexpanded larger configuration under physiological conditions. In anotherexample, the substantially all rings have similar one or more of: radialstrain initially and subsequently, further expansion, radial contractionand/or expansion, similar uncaging, similar displacement, similar changein shape configuration, in the expanded configuration underphysiological conditions. In another example, some rings have differentone or more of: radial strain after expansion, displacement magnitude,shape configuration, contraction and/or expansion, vaso-reactivity, inthe expanded configuration under physiologic conditions.

In another example, the stent prosthesis is configured to uncage,wherein uncaging comprises one or more of: having variable compliance(radial strain) after expansion, having controlled compliance (radialstrain) after expansion that is different from the radial complianceupon expansion, having adaptive to lumen or vessel compliance (radialstrain) after expansion, having variable displacement, having controlleddisplacement different from initial expanded configuration, havingadaptive to lumen or vessel displacement after expansion or deployment,having variable movement, having controlled movement, having adaptive tolumen or vessel movement after expansion, and/or allowingvaso-reactivity after expansion, after said stent expands from a crimpedconfiguration to an expanded configuration under physiologic conditions.

In another example of any of the examples in this application, at leastsome circumferential structural elements (such as rings) or the implantor stent prosthesis after expansion has a composite radial strain (orcompliance) ranging from 1% to 20%, preferably ranging between 1% and15%, more preferably ranging from 1.5% to 10%, most preferably rangingfrom 2% to 7%. In another example the radial strain magnitude rangesfrom 0.07 mm to 3 mm, preferably ranging from 0.1 mm to 2 mm, morepreferably ranging from 0.1 mm to 1 mm, and most preferably ranging from0.1 mm to 0.5 mm In another example the vaso-reactivity magnitude rangesfrom 0.07 mm to 3 mm, preferably ranging from 0.1 mm to 2 mm, morepreferably ranging from 0.1 mm to 1 mm, and most preferably ranging from0.1 mm to 0.5 mm.

One skilled in the art would appreciate the various examples and aspectsdescribed in this application can be employed to facilitate movement inradial, and/or circumferential, or other direction, or combinationthereof.

As with prior examples or embodiments, the male element will typicallybe free to move circumferentially between opposed walls of the femalecoupling member to allow circumferential expansion (and/or radial)and/or contraction of the stent prosthesis. The male segment and thefemale coupling element may be separated by a gap, and the gaps may beleft open or conversely may be filled with a material such as anelastomeric cushion material which dampens the circumferential movementof the male element between opposed walls of the circumferential ring.

As one of skill in the art would appreciate, the various examples andembodiments and aspects described and claimed herein can be combined inpart or in whole throughout this application.

The following numbered clauses describe other examples, aspects, andembodiments of the inventions described herein:

1. An endoluminal prosthesis comprising: a circumferential scaffoldpatterned from a biodegradable polymer and having expansion regionswhich deform as the circumferential scaffold expands from a smalldiameter configuration to a large diameter configuration; and at leastone reinforcement elements coupled to the circumferential scaffold tostiffen the circumferential scaffold after the scaffold has expanded tothe large diameter configuration.

2. An endoluminal prosthesis as in clause 1, wherein at least some ofthe reinforcement elements are coupled to at least some of the expansionregions.

3. An endoluminal prosthesis as in clause 1 or 2, wherein thecircumferential scaffold has non-deformable regions which substantiallyretain their shape as the circumferential scaffold expands.

4. An endoluminal prosthesis as in clause 3, wherein at least some ofthe reinforcement elements are coupled to at least some of thenon-deformable regions.

5. An endoluminal prosthesis as in clause 3, wherein the expansionregions are curved and the non-deformable regions are straight.

6. An endoluminal prosthesis as in clause 5, wherein the curvedexpansion regions are substantially C-shaped, V-shaped, or U-shapedhinges and the non-deformable regions are struts.

7. An endoluminal prosthesis as in clause 3, wherein at least some ofthe reinforcement elements are coupled to both an expansion region and anon-deformable region.

8. An endoluminal prosthesis as in clause 1, wherein at least some ofthe reinforcement are embedded in at least some of the expansionregions.

9. An endoluminal prosthesis as in clause 1 or 2, wherein at least someof the reinforcement elements are disposed at least partly on anexterior of at least some of the expansion regions.

10. An endoluminal prosthesis as in clause 3, wherein at least some ofthe reinforcement span and are embedded in at least some of theexpansion regions and an adjacent non-deformable region.

11. An endoluminal prosthesis as in clause 1, wherein individualreinforcement elements span and are disposed at least partly or anexterior of at least some of the expansion regions and an adjacentnon-deformable region.

12. An endoluminal prosthesis as in clause 1, wherein thecircumferential scaffold comprises a plurality of adjacent rings,wherein the expansion regions comprise curved regions in the rings whichstraighten as the scaffold is radially expanded.

13. An endoluminal prosthesis as in clause 12, wherein the scaffoldrings are serpentine rings.

14. An endoluminal prosthesis as in clause 13, wherein the scaffoldrings are zig-zag rings.

15. An endoluminal prosthesis as in clause 13, wherein individualreinforcement elements are coupled to curves and do not span straightnon-deformable regions.

16. An endoluminal prosthesis as in clause 13, wherein individualreinforcement elements span both curves and straight non-deformableregions.

17. An endoluminal prosthesis as in clause 12, wherein the at least onereinforcement element circumscribes substantially an entirecircumferential length of at least some of the rings but have at leastone break.

18. An endoluminal prosthesis as in clause 12, wherein the at least onereinforcement element circumscribes substantially an entirecircumferential length of at least some of the rings but has at leastone break after the polymeric material of the circumferential scaffoldhas degraded in at least one location.

19. An endoluminal prosthesis as in clause 12, wherein there are aplurality of reinforcement elements circumscribing substantially anentire circumferential length of at least some of the rings but eachreinforcement element has a at least one break.

20. An endoluminal prosthesis as in clause 12, wherein there are aplurality of reinforcement elements circumscribing substantially anentire circumferential length of at least some of the rings but eachreinforcement element has a at least one break after the circumferentialscaffold has degraded.

21. An endoluminal prosthesis as in any one of clauses 17-20, whereinthe at least one break decreases the resistance of the reinforcementelement to radial expansion.

22. An endoluminal prosthesis as in clause 12, wherein thecircumferential scaffold further comprises axial links which hold theadjacent rings together and form closed cells.

23. An endoluminal prosthesis as in clause 18, wherein at least some ofthe reinforcement elements are coupled to at least some axial links.

24. An endoluminal prosthesis as in clause 23, wherein the individualreinforcement elements comprise box structures which are coupled to twosubstantially parallel rings and two substantially parallel axial links.

25. An endoluminal prosthesis as in clause 1, wherein the biodegradablepolymer is selected from a group as set forth in the specification.

26. An endoluminal prosthesis as in clause 1, wherein the reinforcementelements comprise a non-degradable material.

27. An endoluminal prosthesis as in clause 26, wherein the reinforcementelements comprise a non-degradable polymer.

28. An endoluminal prosthesis as in clause 26, wherein the reinforcementelement comprises a metal or metal alloy.

29. An endoluminal prosthesis as in clause 28, wherein the metal isselected from a group consisting of stainless steel, shape memoryalloys, cobalt chromium alloy, platinum chromium alloy, and others asset forth in the specification.

30. An endoluminal prosthesis as in clause 28, wherein the reinforcementelement comprises an elastic material coupled to an expansion region andbiased to open the expansion region after the circumferential scaffoldhas been deployed.

31. An endoluminal prosthesis as in clause 26, wherein the reinforcementelements comprise V-shaped springs coupled to V-shaped expansionregions, C-shaped springs attached to C-shaped expansion regions, orU-shaped springs attached to U-shaped expansion regions.

32. An endoluminal prosthesis comprising: a scaffold havingcircumferential rings patterned from a non-degradable material, saidscaffold being configured to expand from a crimped configuration to anexpanded configuration; wherein at least some of the circumferentialrings have separation regions configured to form discontinuities in saidcircumferential rings in response to energy applied to the separationregions after deployment.

33. An endoluminal prosthesis as in clause 32, wherein thediscontinuities form after implantation of said prosthesis in a bodylumen, whereby the discontinuities allow the scaffold further expandbeyond the initial expansion.

34. An endoluminal prosthesis as in clause 32, wherein the separationregions are configured to fatigue and separate in response.

35. An endoluminal prosthesis as in clause 32, wherein the separationregions are configured to fatigue in response to an externally appliedenergy source.

36. An endoluminal prosthesis as in clause 34 or 35, wherein theseparation regions comprise notches or thinned regions in thecircumferential rings which preferentially fatigue and break in responseto applied energy.

37. An endoluminal prosthesis as in clause 34 or 35, wherein theseparation regions comprise living hinges which cycle open and closed inresponse to the energy to fatigue and break.

38. An endoluminal prosthesis as in clause 34 or 35, wherein theseparation regions comprise modified grain boundaries in metalcircumferential rings which preferentially fatigue and break in responseto applied energy.

39. An endoluminal prosthesis as in clause 34 or 35, wherein theseparation regions are formed by breaking circumferential rings at oneor more sites over their circumference and rejoining the breaks withconnectors which are configured to open in response to applied energy.

40. An endoluminal prosthesis as in clause 39, wherein the connectorswill break in response to externally applied energy selected from thegroup consisting of ultrasound, heat, and magnetism.

41. An endoluminal prosthesis as in clause 34 or 35, wherein theseparation regions comprise a key and lock junction formed in thecircumferential rings, wherein said key and lock junctions areimmobilized during expansion but configured to open in response toapplied energy.

42. An endoluminal prosthesis as in clause 34 or 35, wherein theseparation regions comprise a rivet or other fastener joining breaks inthe circumferential element and configured to open in response toapplied energy.

43. An endoluminal prosthesis a sin clause 32, wherein thecircumferential rings comprise serpentine rings.

44. An endoluminal prosthesis as in clause 32, wherein thecircumferential rings comprise zig-zag rings.

45. An endoluminal prosthesis as in clause 32, wherein thenon-degradable material comprises a metal or a metal alloy.

46. An endoluminal prosthesis as in clause 45, wherein the metalselected from a group consisting of stainless steel, and other metalsset forth in the specification.

47. An endoluminal prosthesis comprising: a scaffold havingcircumferential rings patterned from a non-degradable material, saidscaffold being configured to expand from a crimped configuration to anexpanded configuration; wherein at least some of the circumferentialrings have at least one separation region configured to formdiscontinuities in said circumferential rings after expansion in aphysiologic environment.

48. An endoluminal prosthesis as in clause 47, wherein discontinuitiesallow the scaffold further expand beyond the initial expansion.

49. An endoluminal prosthesis as in clause 48, wherein the physiologicenvironment is a water bath, water at 37° C., or a body lumen.

50. An endoluminal prosthesis as in clause 47, wherein the physiologicenvironment is a body lumen.

51. An endoluminal prosthesis as in clause 47, wherein the body lumen isa blood vessel.

52. An endoluminal prosthesis as in clause 47, wherein thediscontinuities in the rings allow the scaffold to circumferentiallyopen as the blood vessel positively remodels.

53. An endoluminal prosthesis as in clause 47, wherein the separationregions comprise key and lock junctions which are immobilized duringexpansion but configured to separate after the initial expansion in thephysiologic environment.

54. An endoluminal prosthesis as in clause 53, wherein the key and lockjunction is cemented by a material which degrades in the physiologicenvironment.

55. An endoluminal prosthesis as in clause 47, wherein the separationregions comprise a butt joint joined by an adhesive or connector whichdegrades in the physiologic environment.

56. An endoluminal prosthesis as in clause 47, wherein the separationregions comprise notches or thinned sections in the circumferentialrings which preferentially erode in the physiologic environment.

57. An endoluminal prosthesis as in clause 47, wherein the separationregions comprise modified grain boundaries in metal circumferentialrings which preferentially erode in the physiologic environment.

58. An endoluminal prosthesis as in clause 47, wherein the separationregions are formed by breaking circumferential rings at one or moresites over their circumference and rejoining the breaks with adhesivesor connectors which are configured to erode in the physiologicenvironment.

59. An endoluminal prosthesis as in clause 58, wherein the connectorscomprise sleeves or rings spanning the breaks.

60. An endoluminal prosthesis as in clause 47, wherein the separationregions comprise a rivet or other fastener joining breaks in thecircumferential ring, wherein the fastener erodes in the physiologicembodiment.

61. An endoluminal prosthesis as in clause 47, wherein thecircumferential rings comprise serpentine rings.

62. An endoluminal prosthesis as in clause 45, wherein thecircumferential rings comprise zig-zag rings.

63. An endoluminal prosthesis as in clause 45, wherein thenon-degradable material comprises a metal.

64. An endoluminal prosthesis as in clause 47, wherein the metal isselected from a group consisting of stainless steel, and the metals setforth in the specification.

65. An endoluminal prosthesis as in clause 47, wherein there is one ormore separation regions on at least some rings wherein the separationregions are located on crowns, and/or struts.

66. An endoluminal prosthesis as in clause 47, wherein the separationregions locations and number are configured to allow positive lumenremodeling.

67. An endoluminal prosthesis as in clause 65, wherein additionally theweight of the stent prosthesis after deployment in physiologicenvironment allows for positive lumen remodeling.

68. An endoluminal prosthesis as in clause 47, wherein the separationregion provides uncaging of the stent prosthesis after deployment in aphysiologic environment.

69. An endoluminal prosthesis as in clause 68, wherein the stentprosthesis uncages in a circumferential direction.

70. An endoluminal prosthesis comprising: a scaffold havingcircumferential rings patterned from a non-degradable material, saidscaffold being configured to deploy from a crimped configuration to anexpanded configuration and said circumferential rings having hingeswhich open as the scaffold is being deployed; wherein at least some ofthe hinges on at least some of the rings are constricted from expansionduring deployment and are configured to open in a physiologicenvironment after deployment or in response to the application ofinternal or external energy after deployment.

71. An endoluminal prosthesis as in clause 70, wherein the scaffold isreleased to further expand circumferentially after said hinges areopened.

72. An endoluminal prosthesis as in clause 70, wherein the wherein thephysiologic environment is a water bath, water at 37° C., or a bodylumen.

73. An endoluminal prosthesis as in clause 70, wherein the physiologicenvironment is a body lumen.

74. An endoluminal prosthesis as in clause 73, wherein the body lumen isa blood vessel.

75. An endoluminal prosthesis as in clause 74, wherein the scaffold iscircumferentially released to open as the blood vessel positivelyremodels.

76. An endoluminal prosthesis as in clause 70, wherein the hinges open30 days to 6 months after the initial expansion of the circumferentialscaffold.

77. An endoluminal prosthesis as in clause 70, wherein the hinges areconstricted by one or more of adhesives, polymer filaments and polymersleeves.

78. An endoluminal prosthesis as in clause 70, wherein thenon-degradable material comprises a metal or a metal alloy as set forthin the specification.

79. An endoluminal prosthesis comprising: a scaffold havingcircumferential rings patterned from a non-degradable material, saidscaffold being configured to deploy from a crimped configuration to anexpanded configuration and said circumferential rings including strutsconnected by joints which open as the scaffold is being deployed;wherein at least some of the joints are pivoted to allow the scaffold inits expanded configuration to further expand.

80. An endoluminal prosthesis as in any of the independent clauses,wherein the stent prosthesis further comprises non-degradable radiopaquemarkers.

81. An endoluminal prosthesis as in any of the independent clauses,wherein the stent comprises at least one coating on at least one surfaceof the stent

82. An endoluminal prosthesis as in any of the independent clauses,wherein the stent prosthesis comprises at least one drug.

83. An endoluminal prosthesis as in 82, wherein the drug tissueconcentration adjacent to the stent lasts beyond the time period ofun-caging the stent, forming the discontinuity, and/or breaking of thestent.

84. An endoluminal prosthesis comprising: a scaffold having one or morecircumferential rings patterned from a non-degradable material, saidscaffold being configured to expand from a crimped configuration to anexpanded configuration; wherein one or more of the circumferential ringscomprises a plurality of struts joined by crowns and at least one of thestruts has at least one separation region configured to form adiscontinuity in said circumferential ring(s) after expansion in aphysiologic environment.

85. An endoluminal prosthesis as in clause 84, wherein discontinuitiesallow the scaffold further expand after an initial expansion.

86. An endoluminal prosthesis as in clause 84, wherein the physiologicenvironment is a water bath at about 37° C., or a body lumen.

87. An endoluminal prosthesis as in clause 84, wherein the physiologicenvironment is a body lumen.

88. An endoluminal prosthesis as in clause 84, wherein the body lumencomprises a blood vessel or valve annulus.

89. An endoluminal prosthesis as in clause 88, wherein the discontinuityin the ring allows at least a portion of the scaffold tocircumferentially open within the body lumen after deployment.

90. An endoluminal prosthesis as in clause 84, wherein thediscontinuities form 30 days to 6 months after the initial expansion ofthe circumferential scaffold in the physiologic environment.

91. An endoluminal prosthesis as in clause 84, wherein the separationregions comprise key and lock junctions in the struts which areimmobilized during expansion but configured to open after the initialexpansion in the physiologic environment.

92. An endoluminal prosthesis as in clause 91, wherein the key and lockjunctions are configured to allowed the joined segments of the strut toseparate from each other in a radial direction only after they aremobilized.

93. An endoluminal prosthesis as in clause 91, wherein the key and lockjunctions are configured to allowed the joined segments of the strut toseparate from each other in both a radial direction and an axialdirection after they are mobilized.

94. An endoluminal prosthesis as in clause 91, wherein the key and lockjunctions are immobilized by a cement, adhesive, or polymer whichdegrades in the physiologic environment.

95. An endoluminal prosthesis as in clause 91, wherein the key and lockjunctions are immobilized by an overlying a sleeve which degrades in thephysiologic environment.

96. An endoluminal prosthesis as in clause 84, wherein the separationregions comprise a butt joint joined by an adhesive, cement, polymer,sleeve, or connector which degrades in the physiologic environment.

97. An endoluminal prosthesis as in clause 84, wherein the separationregions comprise notches or thinned sections in the circumferentialrings which preferentially erode in the physiologic environment.

98. An endoluminal prosthesis as in clause 84, wherein the separationregions comprise modified grain boundaries in metal circumferentialrings which preferentially erode in the physiologic environment.

99. An endoluminal prosthesis as in clause 84, wherein the separationregions are formed by breaking circumferential rings at one or moresites over their circumference and rejoining the breaks with cement,adhesive, or polymer which are configured to erode in the physiologicenvironment.

100. An endoluminal prosthesis as in clause 99, wherein the connectorscomprise sleeves or rings spanning the breaks.

101. An endoluminal prosthesis as in clause 84, wherein the separationregions comprise a rivet or other fastener joining breaks in thecircumferential ring, wherein the fastener erodes in the physiologicembodiment.

102. An endoluminal prosthesis as in clause 84, wherein thecircumferential rings comprise serpentine rings.

103. An endoluminal prosthesis as in clause 84, wherein thecircumferential rings comprise zig-zag rings.

104. An endoluminal prosthesis as in clause 84, wherein thenon-degradable material comprises a metal.

105. An endoluminal prosthesis as in clause 84, wherein the scaffoldfurther comprises a coating on at least one surface of the scaffold.

106. An endoluminal prosthesis as in clause 84, wherein the scaffoldfurther comprises a coating on at least one surface of the scaffold, andwherein the coating comprises a drug.

107. An endoluminal prosthesis as in clause 84, wherein the scaffold inthe expanded configuration has sufficient strength to support a bodylumen.

108. An endoluminal prosthesis comprising: a scaffold havingcircumferential rings patterned from a non-degradable material, saidscaffold being configured to expand from a crimped configuration to anexpanded configuration; wherein at least some of the circumferentialrings comprise a plurality of struts joined by crowns and at least someof struts have at least one separation region wherein the strut has apre-formed break which is immobilized by a sleeve or an adhesive whichwill degrade in a physiologic environment.

109. An endoluminal prosthesis as in clause 108, wherein the separationregions comprise key and lock junctions in the struts which areimmobilized during expansion but configured to open after the initialexpansion in the physiologic environment.

110. An endoluminal prosthesis as in clause 109, wherein the key andlock junctions are configured to allowed the joined segments of thestrut to separate from each other in a radial direction only after theyare mobilized.

111. An endoluminal prosthesis as in clause 109, wherein the key andlock junctions are configured to allowed the joined segments of thestrut to separate from each other in both a radial direction and anaxial direction after they are mobilized.

112. An endoluminal prosthesis as in clause 109, wherein the key andlock junctions are immobilized by a cement which degrades in thephysiologic environment.

113. An endoluminal prosthesis as in clause 109, wherein the key andlock junctions are immobilized by an overlying a sleeve which degradesin the physiologic environment.

114. An endoluminal prosthesis a sin clause 108, wherein thecircumferential rings comprise serpentine rings.

115. An endoluminal prosthesis as in clause 108, wherein thecircumferential rings comprise zig-zag rings.

116. An endoluminal prosthesis as in clause 108, wherein thenon-degradable material comprises a metal or a metal alloy.

117. An endoluminal prosthesis as in clause 116, wherein the metalselected from a group consisting of stainless steel, and other metalsset forth in the specification.

118. An endoluminal prosthesis as in clause 108, wherein at least onestrut on each ring has a separation region.

119. An endoluminal prosthesis as in clause 118, wherein all crowns andlinks are free from separation regions.

120. An endoluminal prosthesis as in clause 118, wherein the separationregions locations and number are configured to allow positive lumenremodeling.

121. An endoluminal prosthesis as in clause 119, wherein additionallythe weight of the stent prosthesis after deployment in physiologicenvironment allows for positive lumen remodeling.

122. An endoluminal prosthesis as in clause 108, wherein the separationregion provides uncaging of the stent prosthesis after deployment in aphysiologic environment.

123. An endoluminal prosthesis as in clause 122, wherein the stentprosthesis uncages in a circumferential direction.

124. An endoluminal prosthesis comprising: a scaffold havingcircumferential rings patterned from a non-degradable material, saidscaffold being configured to expand from a crimped configuration to anexpanded configuration; wherein at least some of the circumferentialrings comprise a plurality of struts joined by crowns and at least someof crowns have at least one separation region which is immobilized by asleeve or an adhesive which will degrade in a physiologic environment.

125. An endoluminal prosthesis as in clause 124, wherein the separationregion comprises a thinned region in the crown(s) allowing the scaffoldto uncage after degradation of the sleeve or the adhesive material.

126. An endoluminal prosthesis as in clause 122, wherein the separationregion is a break in the crowns allowing the scaffold to uncage afterdegradation of the sleeve or the adhesive material.

Gap Clauses

127. An endovascular prosthesis comprising: a scaffold having aplurality of rings which define a circumference of the scaffold, saidscaffold being configured to expand from a crimped configuration to anexpanded configuration and the plurality of rings are formed from anon-degradable material; wherein at least some of the circumferentialrings follow a circumferential path about the circumference of thescaffold and have at least one gap in said path when the scaffold is inits expanded configuration and wherein adjacent rings are axially linkedso that all portions of the scaffold remain connected when the scaffoldis in its expanded configuration.

128. An endovascular prosthesis as in clause 127, wherein the gaps areopen in the rings when the scaffold is in its crimped configuration.

129. An endovascular prosthesis as in clause 128, wherein the gaps inthe rings open further when the scaffold is in its expandedconfiguration

130. An endovascular prosthesis as in clause 127, wherein the gaps areopen in the rings only after the scaffold is in its expandedconfiguration.

131. An endovascular prosthesis as in clause 127, wherein the gaps inthe circumferential rings are rotationally staggered.

132. An endovascular prosthesis as in clause 131, wherein thecircumferential rings are axially linked in a staggered pattern which isrotationally offset from the staggered gap pattern.

133. An endovascular prosthesis as in clause 127, wherein thecircumferential rings comprise serpentine rings.

134. An endovascular prosthesis as in clause 127, wherein thecircumferential rings comprise zig-zag rings.

135. An endovascular prosthesis as in clause 127, wherein thenon-degradable material comprises a metal.

136. An endovascular prosthesis as in clause 128, wherein thecircumferential rings comprise a plurality of struts joined by crowns.

137. An endovascular prosthesis as in clause 136, wherein the gaps arepresent in the crowns.

138. An endovascular prosthesis as in clause 127, wherein the gaps arepresent in the struts.

139. An endovascular prosthesis as in clause 127, wherein the gaps spana crown and a strut.

140. An endovascular prosthesis as in clause 127, wherein the scaffolddisplays a compliance from 1% to 5%, often from 1% to 3%, when subjectedto systolic/diastolic pressure cycling.

Bridge Clauses

141. An endovascular prosthesis comprising: a scaffold having aplurality of rings which define a circumference of the scaffold, saidscaffold being configured to expand from a crimped configuration to anexpanded configuration and the plurality of rings are formed from anon-degradable material; wherein at least some of the circumferentialrings follow a circumferential path about the circumference of thescaffold and have at least one biodegradable segment in said path andwherein adjacent rings are axially linked so that all portions of thescaffold remain connected after the biodegradable segments in thescaffold have degraded.

142. An endovascular prosthesis as in clause 141, wherein thebiodegradable segments are configured to remain intact while thescaffold is expanded in a vascular environment and to form gaps in therings after the segments have degraded in the vascular environment.

143. An endovascular prosthesis as in clause 141, wherein thebiodegradable segments are configured to degrade in a vascularenvironment over a time period in the range from 3 months to 3 years.

144. An endovascular prosthesis as in clause 141, wherein thebiodegradable segments in the circumferential rings are rotationallystaggered.

145. An endovascular prosthesis as in clause 144, wherein thecircumferential rings are axially linked in a staggered pattern which isrotationally offset from the staggered gap pattern.

146. An endovascular prosthesis as in clause 141, wherein thecircumferential rings comprise serpentine rings.

147. An endovascular prosthesis as in clause 141, wherein thecircumferential rings comprise zig-zag rings.

148. An endovascular prosthesis as in clause 141, wherein thenon-degradable material comprises a metal.

149. An endovascular prosthesis as in clause 148, wherein thebiodegradable segments comprises a biodegradable polymer.

150. An endovascular prosthesis as in clause 141, wherein thecircumferential rings comprise a plurality of struts joined by crowns.

151. An endovascular prosthesis as in clause 150, wherein thebiodegradable segments are present in the crowns.

152. An endovascular prosthesis as in clause 141, wherein thebiodegradable segments are present in the struts.

153. An endovascular prosthesis as in clause 141, wherein thebiodegradable segments span a crown and a strut.

154. An endovascular prosthesis as in clause 141, wherein the scaffolddisplays a radial compliance often from 1.2% to 3%, or more often from1.2% to 3% in its expanded configuration without the biodegradablesegments when subjected to systolic/diastolic pressure cycling.

155. An endovascular prosthesis as in clause 154, wherein the scaffolddisplays a compliance from 1% to 5%, often between 1% to 3%, in itsexpanded configuration with the biodegradable segments in place whensubjected to systolic/diastolic pressure cycling.

Method of Making Clauses

156. A method of making an endovascular prosthesis, said methodcomprising: fabricating a first scaffold having a plurality of ringswhich define a circumference of the scaffold, wherein the plurality ofrings are formed from a non-degradable material; fabricating a secondscaffold having a plurality of rings which define a circumference of thescaffold, wherein the plurality of rings are formed from a biodegradablematerial and wherein the first and second scaffolds have identicalgeometries; forming gaps in portions of at least some of the rings ofthe first scaffold; cutting segments from the second scaffold, whereinthe segments are selected to fill in the gaps in the first scaffold; andsecuring the segments cut from the second scaffold into the gaps formedin the first scaffold.

157. A method of making an endovascular prosthesis as in clause 156,wherein the biodegradable material is selected to remain intact whilethe scaffold is expanded in a vascular environment and to form gaps inthe rings after the segments have degraded in the vascular environment.

158. A method of making an endovascular prosthesis as in clause 156,wherein the biodegradable material is selected to degrade in a vascularenvironment over a time period in the range from 3 months to 3 years.

159. A method of making an endovascular prosthesis as in clause 156,wherein the gaps in the circumferential rings of the first scaffold arerotationally staggered.

160. A method of making an endovascular prosthesis as in clause 159,wherein the circumferential rings in the first scaffold are axiallylinked in a staggered pattern which is rotationally offset from thestaggered gap pattern.

161. A method of making an endovascular prosthesis as in clause 156,wherein the circumferential rings in the first scaffold compriseserpentine rings.

162. A method of making an endovascular prosthesis as in clause 156,wherein the circumferential rings in the first scaffold comprise zig-zagrings.

163. A method of making an endovascular prosthesis as in clause 156,wherein the non-degradable material comprises a metal.

164. An endovascular prosthesis as in clause 163, wherein thebiodegradable material comprises a biodegradable polymer.

165. A method of making an endovascular prosthesis as in clause 156,wherein the circumferential rings comprise a plurality of struts joinedby crowns.

166. A method of making an endovascular prosthesis as in clause 165,wherein the gaps are present in the crowns.

167. A method of making an endovascular prosthesis as in clause 156,wherein the gaps are present in the struts.

Alternative Clauses

168. A degradable stent prosthesis comprising: a circumferentialscaffold patterned from a biodegradable material and having expansionregions which deform as the circumferential scaffold expands from asmall diameter configuration to a larger diameter configuration; and atleast one reinforcement element is coupled to the circumferentialscaffold to stiffen the circumferential scaffold after the scaffold hasexpanded to the large diameter configuration.

169. A stent prosthesis as in clause 168, wherein the stent prosthesiscomprises an endoluminal prosthesis.

170. A stent prosthesis as in clause 168, wherein the small diameter isthe crimped configuration, and wherein the larger expanded diameter isthe deployed configuration.

171. A stent prosthesis as in clause 168, wherein the degradablematerial comprises polymeric material.

172. A stent prosthesis as in clause 168, wherein the degradablematerial comprises metal or metal alloy.

173. A stent prosthesis as in clause 168, wherein the degradablematerial is a polymeric material comprises one or more of: lactides,caprolactones, trimethylene carbonate, glycolides, poly(L-lactide),poly-DL-Lactide, polylactide-co-glycolide (e.g.,poly(L-lactide-co-glycolide), poly(L-lactide-co-epsilon-caprolactone(e.g., weight ratio of from around 50 to around 95% L-lactide to about50 to about 5% caprolactone; poly (L-lactide-co-trimethylene carbonate),polytrimethylene carbonate, poly-caprolactone,poly(glycolide-trimethylene carbonate),poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids, polymers, blends, and/or co-polymers, orcombination thereof.

174. A stent prosthesis as in clause 168, wherein the degradablematerial is metal or metal alloy comprising magnesium.

175. A stent prosthesis as in clause 168, wherein at least some of thereinforcement elements are coupled to at least some of the expansionregions.

176. A stent prosthesis as in clause 168, wherein substantially allexpansion regions are coupled to reinforcement elements.

177. A stent prosthesis as in clause 168, wherein substantially mostexpansion regions are coupled to reinforcement elements.

178. A stent prosthesis as in clause 168, wherein at least half of theexpansion regions are coupled to reinforcement elements.

179. A stent prosthesis as in clause 168 or 175, wherein thecircumferential scaffold has non-deformable regions which substantiallyretain their shape as the circumferential scaffold expands.

180. A stent prosthesis as in clause 179, wherein at least some of thereinforcement elements are coupled to at least some of thenon-deformable regions.

181. A stent prosthesis as in clause 179, wherein the expansion regionsare curved and the non-deformable regions are straight.

182. A stent prosthesis as in clause 181, wherein the curved expansionregions are substantially C-shaped, V-shaped, or U-shaped hinges and thenon-deformable regions are struts.

183. A stent prosthesis as in clause 179, wherein at least some of thereinforcement elements are coupled to both an expansion region and anon-deformable region.

184. A stent prosthesis as in clause 168, wherein at least some of thereinforcement are embedded in at least some of the expansion regions.

185. A stent prosthesis as in clause 168 or 175, wherein at least someof the reinforcement elements are disposed at least partly on anexterior of at least some of the expansion regions.

186. A stent prosthesis as in clause 179, wherein at least some of thereinforcement span and are embedded in at least some of the expansionregions and an adjacent non-deformable region.

187. A stent prosthesis as in clause 168, wherein individualreinforcement elements span and are disposed at least partly on anexterior of at least some of the expansion regions and an adjacentnon-deformable region.

188. A stent prosthesis as in clause 168, wherein the circumferentialscaffold comprises a plurality of adjacent rings, wherein the expansionregions comprise curved regions in the rings which straighten as thescaffold is radially expanded, and wherein the curved regions joinsubstantially straight non deformable regions in the rings.

189. A stent prosthesis as in clause 188, wherein the scaffold rings areserpentine rings.

190. A stent prosthesis as in clause 188, wherein the scaffold rings arezig-zag rings.

191. A stent prosthesis as in clause 188, wherein individualreinforcement elements are coupled to curved regions and do not spanstraight non-deformable regions.

192. A stent prosthesis as in clause 188, wherein the scaffold patternis closed cell pattern.

193. A stent prosthesis as in clause 188, wherein individualreinforcement elements span both curves and straight non-deformableregions.

194. A stent prosthesis as in clause 188, wherein individualreinforcement elements span the curved regions and at least some of thenon-deformable regions.

195. A stent prosthesis as in clause 188, wherein the at least onereinforcement element circumscribes substantially an entirecircumferential length of at least some of the rings but have at leastone break in each ring.

196. A stent prosthesis as in clause 188, wherein the at least onereinforcement element per ring circumscribes substantially an entirecircumferential length of at least some of the rings but have at leastone break in each ring.

197. A stent prosthesis as in clause 188, wherein the adjacent rings areconnected in at least one region by a link, and wherein at least one ofthe links are coupled to the at least one reinforcement element.

198. A stent prosthesis as in clause 188, wherein the at least onereinforcement element circumscribes substantially an entirecircumferential length of at least some of the rings but has at leastone break after the degradable material of the circumferential scaffoldhas degraded in at least one location.

199. A stent prosthesis as in clause 188, wherein the at least onereinforcement element circumscribes substantially an entirecircumferential length of at least some of the rings but has at leastone break after the degradable material of the circumferential scaffoldhas degraded in the at least one break region.

200. A stent prosthesis as in clause 188, wherein there are a pluralityof reinforcement elements circumscribing substantially an entirecircumferential length of at least some of the rings but eachreinforcement element has a at least one break.

201. A stent prosthesis as in clause 188, wherein there are a pluralityof reinforcement elements circumscribing substantially an entirecircumferential length of at least some of the rings but eachreinforcement element has a at least one break after the circumferentialscaffold has degraded.

202. A stent prosthesis as in any one of clauses 195-201, wherein the atleast one break decreases the resistance of the reinforcement element toradial expansion.

203. A stent prosthesis as in any one of clauses 195-201, wherein the atleast one break diminishes the resistance of the reinforcement elementto radial expansion.

204. A stent prosthesis as in clause 188, wherein the circumferentialscaffold further comprises axial links which hold the adjacent ringstogether and form closed cells.

205. A stent prosthesis as in clause 198, wherein at least some of thereinforcement elements are coupled to at least some axial links.

206. A stent prosthesis as in clause 205, wherein the individualreinforcement elements comprise box structures which are coupled to twosubstantially parallel rings and two substantially parallel axial links.

207. A stent prosthesis as in clause 168, wherein the biodegradablematerial is a polymeric material selected from a group as set forth inthe specification.

208. A stent prosthesis as in clause 168, wherein the biodegradablematerial is a metal or metal alloy material selected from a group as setforth in the specification.

209. A stent prosthesis as in clause 168, wherein the reinforcementelements comprise a non-degradable material.

210. A stent prosthesis as in clause 168, wherein the reinforcementelements comprise degradable material, wherein said degradable materialis stiffer than the scaffold patterned biodegradable material.

211. A stent prosthesis as in clause 168, wherein the reinforcementelements comprise a non-degradable polymer.

212. A stent prosthesis as in clause 168, wherein the reinforcementelement comprises a metal or metal alloy.

213. A stent prosthesis as in clause 212, wherein the metal or metalalloy is selected from a group consisting of stainless steel, shapememory alloys, cobalt chromium alloy, platinum chromium alloy, andothers as set forth in the specification.

214. A stent prosthesis as in clause 212, wherein the reinforcementelement comprises an elastic material coupled to an expansion region andbiased to open the expansion region after the circumferential scaffoldhas been deployed.

215. A stent prosthesis as in clause 212, wherein the reinforcementelement comprises an elastic material coupled to two adjacentsubstantially non-deformable regions and biased to open the expansionregion joining the two adjacent non-deformable regions after thecircumferential scaffold has been deployed, and wherein thereinforcement element has an expansion region shape.

216. A stent prosthesis as in clause 168, wherein the reinforcementelement has a substantially similar shape to the expansion region.

217. A stent prosthesis as in clause 168, wherein the stent furthercomprises radiopaque markers.

218. A stent prosthesis as in clause 168, wherein the stent furthercomprises a drug and polymer matrix coating.

219. A stent prosthesis as in clause 168, wherein the stent furthercomprises a coating on at least one surface of the stent.

220. A stent prosthesis as in clause 219, wherein the stent furthercomprises a degradable coating on at least one surface of the stent.

221. A stent prosthesis as in clause 168 or any of the clauses, whereinthe patterned biodegradable scaffold material degrades in a periodranging from 1 month to 3 years.

222. A stent prosthesis as in clause 168 or any of the clauses, whereinthe reinforcement element remains substantially intact after degradationof the stent material.

223. A stent prosthesis as in clause 168, wherein the stent afterexpansion exhibit one or more of: vaso-dilation, vaso-constriction,radial strain of 1.5% to 5%, further expand to a larger configurationafter recoil from said expansion,

224. A stent prosthesis as in clause 168 or any clause, wherein thereinforcement element is degradable material stiffer than the stentbiodegradable patterned material, and wherein the said reinforcementelements degradable material degrades at a rate slower than the stentdegradable material.

225. A stent prosthesis as in clause 168 or any clause, wherein thestent after degradation of the patterned degradable material comprises aplurality of adjacent reinforcement elements in a circumferential and/orlongitudinal direction.

226. A stent as in clause 168, wherein the stent at body temperature isexpanded to the deployed diameter and has sufficient strength to supporta body lumen.

227. A stent as in clause 168, wherein the stent after degradation ofthe patterned material comprises reinforcement elements, said stent doesnot have sufficient strength to support a body lumen.

228. A stent as in clause 168, wherein the stent after degradation ofthe patterned material does not have sufficient strength to support abody lumen, but comprises reinforcement elements in a pattern sufficientto support a body lumen.

229. A stent prosthesis as in clause 168, wherein the reinforcementelements comprise V-shaped springs coupled to V-shaped expansionregions, C-shaped springs attached to C-shaped expansion regions, orU-shaped springs attached to U-shaped expansion regions.

230. An stent prosthesis comprising: a scaffold having circumferentialrings patterned from a non-degradable material, said scaffold beingconfigured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential rings haveseparation regions configured to form discontinuities in saidcircumferential rings in response to energy applied to the separationregions after deployment.

231. A stent prosthesis as in clause 230, wherein the stent is expandedunder physiologic conditions.

232. A stent prosthesis as in clause 230, wherein the discontinuitiesform after implantation of said prosthesis in a body lumen, whereby thediscontinuities allow the scaffold further expand after recoil from saidinitial expansion.

233. A stent prosthesis as in clause 230, wherein the separation regionsare configured to fatigue and separate in response to pulsation of ablood vessel in which the stent prosthesis has been implanted.

234. A stent prosthesis as in clause 233, wherein the separation regionsare contained by a sleeve that continues to substantially contain theseparation regions after the separation.

235. A stent prosthesis as in clause 230, wherein the separation regionsare configured to fatigue and separate in response to physiologicalpressure of a blood vessel in which the stent prosthesis has beenimplanted.

236. A stent prosthesis as in clause 230, wherein the discontinuitiesform after expansion of said scaffold under physiologic conditions,whereby the discontinuities allow the scaffold to have radial complianceranging between 1% and 5%.

237. A stent prosthesis as in clause 230, wherein the discontinuitiesform after expansion of said scaffold under physiologic conditions,whereby the discontinuities allow the scaffold to expand or restrict inresponse to a vaso-dilator or vaso-constrictor.

238. A stent prosthesis as in clause 230, wherein the separation regionsare configured to fatigue in response to an externally applied energysource.

239. A stent as in clause 230 or 233, wherein the energy applied isphysiological conditions.

240. A stent prosthesis as in clause 233 or 238, wherein the separationregions comprise notches, hollowed out expansion regions, or thinnedregions in the circumferential rings which preferentially fatigue andbreak in response to applied energy.

241. A stent prosthesis as in clause 233 or 238, wherein the separationregions comprise living hinges which cycle open and closed in responseto the energy to fatigue and break.

242. A stent prosthesis as in clause 233 or 238, wherein the separationregions comprise modified grain boundaries in metal circumferentialrings which preferentially fatigue and break in response to appliedenergy.

243. A stent prosthesis as in clause 233 or 238, wherein the separationregions are formed by breaking circumferential rings at one or moresites over their circumference and rejoining the breaks with connectorswhich are configured to open in response to applied energy.

244. A stent prosthesis as in clause 243, wherein the connectors willbreak in response to externally applied energy selected from the groupconsisting of ultrasound, heat, and magnetism.

245. A stent prosthesis as in clause 233 or 238, wherein the separationregions comprise a key and lock junction formed in the circumferentialrings, wherein said key and lock junctions are immobilized duringexpansion but configured to open or separate in response to appliedenergy.

246. A stent prosthesis as in clause 233 or 238, wherein the separationregions comprise a rivet or other fastener joining breaks in thecircumferential element and configured to open in response to appliedenergy.

247. A stent prosthesis as in clause 230, wherein the circumferentialrings comprise serpentine rings.

248. A stent prosthesis as in clause 230, wherein the circumferentialrings comprise zig-zag rings.

249. A stent prosthesis as in clause 230, wherein the rings compriseclosed cell pattern.

250. A stent prosthesis as in clause 230, wherein the non-degradablematerial comprises a metal or a metal alloy.

251. A stent prosthesis as in clause 250, wherein the metal selectedfrom a group consisting of stainless steel, cobalt chromium alloy,platinum chromium alloy, and other metals set forth in thespecification.

252. A stent prosthesis comprising; a scaffold having circumferentialrings patterned from a degradable material, said scaffold beingconfigured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential rings haveseparation regions configured to form discontinuities in saidcircumferential rings after deployment of the stent under physiologicalcondition.

253. A stent prosthesis as in clause 252 wherein the degradable materialcomprises a polymeric material or metallic material.

254. A stent prosthesis as in clause 252 or 253 wherein the degradablematerial is one or more of the following: lactides, caprolactones,trimethylene carbonate, glycolides, poly(L-lactide), poly-DL-Lactide,polylactide-co-glycolide (e.g., poly(L-lactide-co-glycolide),poly(L-lactide-co-epsilon-caprolactone (e.g., weight ratio of fromaround 50 to around 95% L-lactide to about 50 to about 5% caprolactone;poly (L-lactide-co-trimethylene carbonate), polytrimethylene carbonate,poly-caprolactone, poly(glycolide-trimethylene carbonate),poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids, polymers, blends, and/or co-polymers, orcombination thereof, Nickel; Cobalt; Tungsten; Tungsten alloys ofrhenium, cobalt, iron, zirconium, zinc, titanium; Magnesium, Magnesiumalloy AZ31, magnesium alloy with less than 20% zinc or aluminum byweight, without or with one or more impurities of less than 3% iron,silicone, manganese, cobalt, nickel, yttrium, scandium or other rareearth metal; zinc or its alloy; bismuth or its alloy; indium or itsalloy, tin or its alloy such as tin-lead; silver or its alloy such assilver-tin alloy; cobalt-iron alloy; iron; iron containing alloys suchas 80-55-06 grade cast ductile iron, other cast ductile irons, AISI 1010steel, AISI 1015 steel, AISI 1430 steel, AISI 8620 steel, AISI 5140steel, or other steels; melt fusible alloys (such as 40% bismuth-60%tin, 58% bismuth-42% tin, bismuth-tin-indium alloys; alloys comprisingone or more of bismuth, indium, cobalt, tungsten, bismuth, silver,copper, iron, zinc, magnesium, zirconium, molybdenum, indium, tin; orother material; or combination thereof.

255. A stent prosthesis comprising: a scaffold having circumferentialrings patterned from a non-degradable material, said scaffold beingconfigured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential rings haveat least one separation region configured to form discontinuities insaid circumferential rings after expansion in a physiologic environment.

256. A stent prosthesis as in clause 255, wherein discontinuities allowthe scaffold further expand beyond the initial expansion, have radialstrain ranging from 1.5% to 5%, or further expand in response to avaso-dilator.

257. A stent prosthesis as in clause 256, wherein the physiologicenvironment is a water bath, water at 37° C., pressure pulsation, or abody lumen.

258. A stent prosthesis as in clause 255, wherein the physiologicenvironment is a body lumen.

259. A stent prosthesis as in clause 255, wherein the body lumen is ablood vessel.

260. A stent prosthesis as in clause 255, wherein the discontinuities inthe rings allow the scaffold to circumferentially open as the bloodvessel positively remodels.

261. A stent prosthesis as in clause 255, wherein the discontinuitiesform 30 days to 6 months after the initial expansion of thecircumferential scaffold in the physiologic environment.

262. A stent prosthesis as in clause 255, wherein the separation regionscomprise key and lock junctions which are immobilized during expansionbut configured to separate after the initial expansion in thephysiologic environment.

263. A stent prosthesis as in clause 262, wherein the key and lockjunction is cemented by a material which degrades in the physiologicenvironment.

264. A stent prosthesis as in clause 255, wherein the separation regionscomprise a butt joint joined by an adhesive or connector which degradesin the physiologic environment.

265. A stent prosthesis as in clause 255, wherein the separation regionscomprise notches or thinned sections in the circumferential rings whichpreferentially erode in the physiologic environment.

266. A stent prosthesis as in clause 255, wherein the separation regionscomprise modified grain boundaries in metal circumferential rings whichpreferentially erode in the physiologic environment.

267. A stent prosthesis as in clause 255, wherein the separation regionsare formed by breaking circumferential rings at one or more sites overtheir circumference and rejoining the breaks with adhesives orconnectors which are configured to erode in the physiologic environment.

268. A stent prosthesis as in clause 267, wherein the connectorscomprise sleeves or rings spanning the breaks.

269. A stent prosthesis as in clause 255, wherein the separation regionscomprise a rivet or other fastener joining breaks in the circumferentialring, wherein the fastener erodes in the physiologic embodiment.

270. A stent prosthesis as in clause 255, wherein the circumferentialrings comprise serpentine rings.

271. A stent prosthesis as in clause 250, wherein the circumferentialrings comprise zig-zag rings.

272. A stent prosthesis as in clause 255, wherein the non-degradablematerial comprises a metal or metal alloy.

273. A stent prosthesis as in clause 255, wherein the metal is selectedfrom a group consisting of stainless steel, and the metals set forth inthe specification.

274. A stent prosthesis as in clause 255, wherein there is one or moreseparation regions on at least some rings wherein the separation regionsare located on crowns, and/or struts.

275. An endoluminal prosthesis as in clause 255, wherein the separationregions locations and number are configured to allow positive lumenremodeling.

276. An endoluminal prosthesis as in clause 274, wherein additionallythe weight of the stent prosthesis after deployment in physiologicenvironment allows for positive lumen remodeling.

277. An endoluminal prosthesis as in clause 255, wherein the separationregion provides uncaging of the stent prosthesis after deployment in aphysiologic environment.

278. An endoluminal prosthesis as in clause 277, wherein the stentprosthesis uncages in a circumferential direction.

279. A stent prosthesis comprising: a scaffold having circumferentialrings patterned from a degradable material, said scaffold beingconfigured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential rings haveat least one separation region configured to form discontinuities insaid circumferential rings after expansion in a physiologic environment.

280. A stent prosthesis as in clause 279, wherein the stent degrades ina period ranging from 3 months to 10 years.

281. A stent prosthesis comprising: a scaffold having circumferentialrings patterned from a polymeric or metallic material, said scaffoldbeing configured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential rings haveat least one separation region forming discontinuities in saidcircumferential rings prior to expansion in a physiologic environment.

282. A stent prosthesis comprising; a scaffold having circumferentialrings patterned from a non-degradable material, said scaffold beingconfigured to deploy from a crimped configuration to an expandedconfiguration and said circumferential rings having hinges which open asthe scaffold is being deployed; wherein at least some of the hinges onat least some of the rings are constricted from expansion duringdeployment and are configured to open in a physiologic environment afterdeployment or in response to the application of internal or externalenergy after deployment.

283. A stent prosthesis as in clause 282, wherein the scaffold isreleased to further expand circumferentially after said hinges areopened.

284. A stent prosthesis as in clause 282, wherein the physiologicenvironment is a water bath, water at 37° C., or a body lumen.

285. A stent prosthesis as in clause 282, wherein the physiologicenvironment is a body lumen.

286. A stent prosthesis as in clause 285, wherein the body lumen is ablood vessel.

287. A stent prosthesis as in clause 286, wherein the scaffold iscircumferentially released to open as the blood vessel positivelyremodels.

288. A stent prosthesis as in clause 282, wherein the hinges open 30days to 6 months after the initial expansion of the circumferentialscaffold.

289. A stent prosthesis as in clause 282, wherein the hinges areconstricted by one or more of adhesives, polymer filaments, and polymersleeves.

290. An endoluminal prosthesis as in clause 282, wherein thenon-degradable material comprises a metal or a metal alloy as set forthin the specification.

291. A stent prosthesis comprising: a scaffold having circumferentialrings patterned from a non-degradable material, said scaffold beingconfigured to deploy from a crimped configuration to an expandedconfiguration and said circumferential rings including struts connectedby joints which open as the scaffold is being deployed; wherein at leastsome of the joints are pivoted to allow the scaffold in its expandedconfiguration to further expand.

292. A stent prosthesis as in any of the independent clauses, whereinthe stent prosthesis further comprises non-degradable radiopaquemarkers.

293. A stent prosthesis as in any of the independent clauses, whereinthe stent comprises at least one coating on at least one surface of thestent

294. A stent prosthesis as in any of the independent clauses, whereinthe stent prosthesis comprises at least one drug.

295. A stent prosthesis as in 294, wherein the drug tissue concentrationadjacent to the stent lasts beyond the time period of un-caging thestent, forming the discontinuity, and/or breaking of the stent.

296. A stent prosthesis comprising: a scaffold having one or morecircumferential rings patterned from a non-degradable material, saidscaffold being configured to expand from a crimped configuration to anexpanded larger configuration; wherein one or more of thecircumferential rings comprises a plurality of struts joined by crownsand at least one of the struts and/or crowns regions have at least oneseparation region configured to form a discontinuity in saidcircumferential ring(s) after expansion in a physiologic environment.

297. A stent prosthesis as in clause 296, wherein discontinuities allowthe scaffold further expand after inward recoil from an initialexpansion.

298. A stent prosthesis as in clause 296, wherein the physiologicenvironment is a water bath at about 37° C., or a body lumen.

299. A stent prosthesis as in clause 296, wherein the physiologicenvironment is a body lumen.

300. A stent prosthesis as in clause 296, wherein the body lumencomprises a blood vessel or valve annulus.

301. A stent prosthesis as in clause 300, wherein the discontinuity inthe ring allows at least a portion of the scaffold to circumferentiallyopen within the body lumen after deployment.

302. A stent prosthesis as in clause 296, wherein the discontinuitiesform 30 days to 6 months after the initial expansion of thecircumferential scaffold in the physiologic environment.

303. A stent prosthesis as in clause 296, wherein the separation regionscomprise key and lock junctions in the struts which are immobilizedduring expansion but configured to open after the initial expansion inthe physiologic environment.

304. A stent prosthesis as in clause 303, wherein the key and lockjunctions are configured to allowed the joined segments of the strut toseparate from each other in a radial direction only after they aremobilized.

305. A stent prosthesis as in clause 303, wherein the key and lockjunctions are configured to allowed the joined segments of the strut toseparate from each other in both a radial direction and an axialdirection after they are mobilized.

306. A stent prosthesis as in clause 303, wherein the key and lockjunctions are configured to allowed the joined segments of the strut toseparate from each other in an axial direction after they are mobilized.

307. A stent prosthesis as in clause 303, wherein the key and lockjunctions are immobilized by solder, adhesive, or polymer which degradesin the physiologic environment.

308. A stent prosthesis as in clause 303, wherein the key and lockjunctions are immobilized by fusing the material together which degradesor fatigues in the physiologic environment.

309. A stent prosthesis as in clause 303, wherein the key and lockjunctions are immobilized by an overlying a sleeve which degrades in thephysiologic environment.

310. A stent prosthesis as in clause 296, wherein the separation regionscomprise

a butt joint joined by an adhesive, solder, polymer, sleeve, fusing thematerial, or connector which degrades or fatigues in the physiologicenvironment.

311. A stent prosthesis as in clause 296, wherein the separation regionscomprise notches or thinned sections in the circumferential rings whichpreferentially erode or fatigue in the physiologic environment.

312. A stent prosthesis as in clause 296, wherein the separation regionscomprise modified grain boundaries in metal circumferential rings whichpreferentially erode or fatigue in the physiologic environment.

313. A stent prosthesis as in clause 296, wherein the separation regionsare formed by breaking circumferential rings at one or more sites overtheir circumference and rejoining the breaks with adhesive, or polymerwhich are configured to erode in the physiologic environment.

314. A stent prosthesis as in clause 313, wherein the connectorscomprise sleeves or rings spanning the breaks.

315. A stent prosthesis as in clause 296, wherein the separation regionscomprise a rivet or other fastener joining breaks in the circumferentialring, wherein the fastener erodes in the physiologic embodiment.

316. A stent prosthesis as in clause 296, wherein the circumferentialrings comprise serpentine rings.

317. A stent prosthesis as in clause 296, wherein the circumferentialrings comprise zig-zag rings.

318. A stent prosthesis as in clause 296, wherein the circumferentialrings comprise closed ring type design.

319. A stent prosthesis as in clause 296, wherein the non-degradablematerial comprises a metal or metal alloy.

320. A stent prosthesis as in clause 296, wherein the scaffold furthercomprises a coating on at least one surface of the scaffold.

321. A stent prosthesis as in clause 296, wherein the scaffold furthercomprises a coating on at least one surface of the scaffold, and whereinthe coating comprises a drug.

322. A stent prosthesis as in clause 296, wherein the scaffold in theexpanded configuration has sufficient strength to support a body lumen.

323. A stent prosthesis comprising: a scaffold having circumferentialrings patterned from a non-degradable material, said scaffold beingconfigured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential ringscomprise a plurality of struts joined by crowns and at least some ofstruts and/or crowns have at least one separation region wherein thestrut has a pre-formed break which is immobilized by a solder, apolymer, a sleeve, or an adhesive which will degrade in a physiologicenvironment.

324. A stent prosthesis as in clause 323, wherein the separation regionscomprise key and lock junctions in the struts and/or crowns which areimmobilized during expansion but configured to open after the initialexpansion in the physiologic environment.

325. A stent prosthesis as in clause 324, wherein the key and lockjunctions are configured to allowed the joined segments of the strutand/or crowns to separate from each other in a radial direction onlyafter they are mobilized.

326. A stent prosthesis as in clause 324, wherein the key and lockjunctions are configured to allowed the joined segments of the strutand/or crowns to separate from each other in a radial direction and/oran axial direction after they are mobilized.

327. A stent prosthesis as in clause 324, wherein the key and lockjunctions are immobilized by a cement which degrades in the physiologicenvironment.

328. A stent prosthesis as in clause 324, wherein the key and lockjunctions are immobilized by an overlying a sleeve which degrades in thephysiologic environment.

329. A stent prosthesis as in clause 323, wherein the circumferentialrings comprise serpentine rings.

330. A stent prosthesis as in clause 323, wherein the circumferentialrings comprise zig-zag rings.

331. A stent prosthesis as in clause 323, wherein the circumferentialrings comprise closed cell (ring) type design.

332. An endoluminal prosthesis as in clause 323, wherein thenon-degradable material comprises a metal or a metal alloy.

333. A stent prosthesis as in clause 332, wherein the metal or metalalloy selected from a group consisting of stainless steel, CobaltChrome, Platinum alloys, and other metals and metal alloys set forth inthe specification.

334. A stent prosthesis as in clause 323, wherein at least one strutand/or crown on each ring has a separation region.

335. A stent prosthesis as in clause 323, wherein at least two strutsand/or crowns on each ring have a separation region.

336. A stent prosthesis as in clause 323, wherein at least three strutsand/or crowns on each ring have a separation region.

337. A stent prosthesis as in clause 323, wherein at least four strutsand/or crowns on each ring have a separation region.

338. A stent prosthesis as in clause 323, wherein substantially allstruts and/or crowns on each ring have a separation region.

339. A stent prosthesis as in clause 334, wherein all crowns and linksare free from separation regions.

340. A stent prosthesis as in clause 334, wherein all links are freefrom separation regions.

341. A stent prosthesis as in clause 334, wherein at least one linkconnecting each two adjacent rings is free from separation regions.

342. A stent prosthesis as in clause 334, wherein at least two linksconnecting each two adjacent rings are free from separation regions.

343. A stent prosthesis as in clause 334, wherein at least three linksconnecting each two adjacent rings are free from separation regions.

344. A stent prosthesis as in clause 334, wherein at least four linksconnecting each two adjacent rings are free from separation regions.

345. A stent prosthesis as in clause 334, wherein each ring is connectedto an adjacent ring by links ranging from 2 to 4 links, and wherein saidlinks are free from separation regions.

346. A stent prosthesis as in clause 334, wherein at least one crownregion of each ring is joined to an adjacent crown region on anotherring, by solder, fusing, or melting, and wherein said crown region has aseparation region uncaging at least one ring.

347. A stent prosthesis as in clause 334, wherein at least two crownregions of each ring is joined to an adjacent two crown regions onanother ring, by solder, fusing, or melting, and wherein said crownregions have a separation region uncaging the two adjacent rings in acircumferential direction.

348. A stent prosthesis as in clause 334, wherein adjacent rings arejoined or linked in one or more locations, and wherein the links areintact at the time of the separation regions separate.

349. A stent prosthesis as in clause 334, wherein adjacent rings arejoined or linked in one or more locations but not all such that thelinks do not form a closed cell design, and wherein the links are intactat the time of the separation regions separate.

350. A stent prosthesis as in clause 323, wherein at least one strutand/or crown on each ring has a separation region, and wherein the stentuncages in a circumferential direction and uncages in the stentlongitudinal direction while the links are substantially intact.

351. A stent prosthesis as in clause 323, wherein at least one strutand/or crown on each ring has a separation region, and wherein each ringof the stent uncages in a circumferential direction and the stentuncages in the longitudinal direction, and wherein the stent prosthesisseparates from 1 to 4 longitudinal sections.

352. A stent prosthesis as in clause 323, wherein at least one strutand/or crown on each ring has a separation region, and wherein the stentuncages in the circumferential direction and uncages in the stentlongitudinal direction while keeping the axial links substantiallyintact, and wherein the stent prosthesis separates from 1 to 4longitudinal sections.

353. A stent prosthesis as in clause 323, wherein at least one strutand/or crown on each ring has a separation region, and wherein the stentuncages in the circumferential direction and separates the stent in thelongitudinal direction spanning from 1 to 5 adjacent rings, whilekeeping the axial links substantially intact, wherein the stentseparates from 2 to 4 sections of said adjacent rings.

354. A stent prosthesis as in clause 323, wherein at least one strutand/or crown on each ring has a separation region, and wherein the stentuncages in the circumferential direction and wherein the stent in thelongitudinal direction remains substantially intact.

355. A stent prosthesis as in clause 323, wherein at least one strutand/or crown on each ring has a separation region, and wherein the stentuncages in the circumferential direction and wherein the stent in thelongitudinal direction remains substantially intact and the axial linksare maintained.

356. A stent prosthesis as in clause 323, wherein at least one strutand/or crown on each ring has a separation region, and wherein the atleast one separation region on each ring forms a discontinuity in eachring, and wherein the stent in the longitudinal direction remainssubstantially intact and the axial links are maintained.

357. A stent prosthesis as in clause 323, wherein at least two strutsand/or crown on each ring have separation regions, and wherein the atleast two separation regions on each ring forms at least twodiscontinuities in each ring, and wherein the stent in the longitudinaldirection remains substantially intact.

358. A stent prosthesis as in clause 323, wherein at least three strutsand/or crown on each ring have separation regions, and wherein the atleast three separation regions on each ring forms at least threediscontinuities in each ring, and wherein the stent in the longitudinaldirection remains substantially intact.

359. A stent prosthesis as in clause 323, wherein at least one strutand/or crown on each ring has a separation region, and wherein the atleast one separation region on each ring forms a discontinuity in saidring, and said stent have one or more separate longitudinal sections,and wherein the links are substantially intact connecting the stent inthe longitudinal direction.

360. A stent prosthesis as in clause 334, wherein the separation regionslocations and number are configured to allow one or more of: stentradial strain between 1% and 5%, stent further expansion after inwardrecoil from first expanded configuration, uncaging the stent in acircumferential direction, allowing the stent to respond (expand orcontract) to a vaso-dilator or vaso-constrictor, or positive lumenremodeling.

361. A stent prosthesis as in clause 339, wherein additionally theweight of the stent prosthesis after deployment in physiologicenvironment allows for positive lumen remodeling

362. A stent prosthesis as in clause 323, wherein the separation regionprovides uncaging of the stent prosthesis after deployment in aphysiologic environment.

363. A stent prosthesis as in clause 362, wherein the stent prosthesisuncages in a circumferential direction.

364. A stent prosthesis comprising: a scaffold having circumferentialrings patterned from a non-degradable material, said scaffold beingconfigured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential ringscomprise a plurality of struts joined by crowns and at least some ofcrowns have at least one separation region which is immobilized by asleeve or an adhesive which will degrade in a physiologic environment.

365. A stent prosthesis as in clause 364, wherein the separation regioncomprises a thinned region in the crown(s) allowing the scaffold touncage after degradation of the sleeve or the adhesive material.

366. A stent prosthesis as in clause 362, wherein the separation regionis a break in the crowns allowing the scaffold to uncage afterdegradation of the sleeve or the adhesive material.

367. A stent prosthesis comprising: a scaffold having circumferentialrings patterned from a degradable material, said scaffold beingconfigured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential ringscomprise a plurality of struts joined by crowns and at least some ofstruts and/or crowns have at least one separation region which isimmobilized by a solder, polymer, sleeve, or an adhesive which willdegrade in a physiologic environment.

368. A stent prosthesis as in clause 367, wherein the degradablematerial is polymeric or metallic.

369. A stent prosthesis as in clause 367, wherein the degradablematerial is metal or metal alloy.

370. A stent prosthesis comprising: a scaffold comprising non-degradablematerial having a plurality of rings which define a circumference of thescaffold, said scaffold being configured to expand from a crimpedconfiguration to an expanded larger configuration; wherein at least oneof the circumferential rings follow a circumferential path about thecircumference of the scaffold and have at least one gap in said pathwhen the scaffold is in its expanded configuration and wherein adjacentrings are axially linked so that all portions of the scaffold remainconnected when the scaffold is in its expanded configuration.

371. A stent prosthesis as in clause 370, wherein each ring defines acircumference of the scaffold

372. A stent prosthesis as in clause 370, wherein at least some of thecircumferential rings follow a circumferential path about thecircumference of the scaffold and have at least one gap in said path ofeach ring.

373. A stent prosthesis as in clause 370, wherein the gaps are open inthe rings when the scaffold is in its crimped configuration.

374. A stent prosthesis as in clause 373, wherein the gaps in the ringsopen further when the scaffold is in its expanded configuration

375. A stent prosthesis as in clause 370, wherein the gaps are open inthe rings only after the scaffold is in its expanded configuration.

376. A stent prosthesis as in clause 370, wherein the gaps in thecircumferential rings are rotationally staggered.

377. A stent prosthesis as in clause 370, wherein there is more than onegap in each of the circumferential rings which are spaced symmetricallyin each ring.

378. A stent prosthesis as in clause 370, wherein there is more than onegap in each of the circumferential rings which are rotationally offsetfrom an adjacent ring.

379. A stent prosthesis as in clause 370, wherein there is more than onegap in each of the circumferential rings which are rotationally offsetfrom an adjacent ring by 45 degrees to 90 degrees.

380. An endovascular prosthesis as in clause 375, wherein thecircumferential rings are axially linked in a staggered pattern which isrotationally offset from the staggered gap pattern.

381. An endovascular prosthesis as in clause 370, wherein thecircumferential rings comprise serpentine rings.

382. An endovascular prosthesis as in clause 370, wherein thecircumferential rings comprise zig-zag rings.

383. An endovascular prosthesis as in clause 370, wherein thecircumferential rings comprise closed cell rings.

384. An endovascular prosthesis as in clause 370, wherein thenon-degradable material comprises a metal or metal alloy.

385. An endovascular prosthesis as in clause 370, wherein thecircumferential rings comprise a plurality of struts joined by crowns.

386. An endovascular prosthesis as in clause 385, wherein the gaps arepresent in the crowns region.

387. An endovascular prosthesis as in clause 370, wherein the gaps arepresent in the struts regions.

388. An endovascular prosthesis as in clause 370, wherein the gaps spana crown and a strut regions.

389. A stent prosthesis as in clause 370, wherein the gaps are presentin the struts region, and wherein the strut end regions adjacent to thegaps are rounded.

390. A stent prosthesis as in clause 370, wherein the gaps are presentin the struts region, and wherein at least one strut region adjacent tothe gap is connected to same or adjacent ring.

391. A stent prosthesis as in clause 370, wherein the gaps are presentin the struts region, and wherein the struts adjacent to the gap overlapalong at least some struts length.

392. A stent prosthesis as in clause 385, wherein the gaps are presentin the crowns and/or struts regions.

393. A stent prosthesis as in clause 385, wherein the gaps are presentin the crowns region, and wherein the crowns adjacent to the gap overlapalong the at least some crown length.

394. A stent prosthesis as in clause 385, wherein the gaps are presentin the crowns regions, and wherein at least one crown region adjacent tothe gap is connected to same or adjacent ring.

395. A stent prosthesis as in clause 370, wherein the stent in theexpanded configuration has sufficient strength to support a body lumen.

396. A stent as in clause 370, wherein the stent strength afterdeployment to the expanded configuration remains substantially the same.

397. A stent prosthesis as in clause 370, wherein the stent patternafter deployment remains substantially the same.

398. A stent prosthesis as in clause 370, wherein the stent furthercomprises radiopaque markers.

399. A stent prosthesis as in clause 370, wherein the stent uncages thebody lumen after deployment

400. A stent prosthesis as in clause 370, wherein the stent is capableof vaso-dilation or vasoconstriction after deployment

401. A stent prosthesis as in clause 370, wherein the scaffold displaysa compliance (radial strain) between 1% to 5% when subjected tosystolic/diastolic pressure cycling.

402. A stent prosthesis comprising: a scaffold comprising a degradablematerial having a plurality of rings which define a circumference of thescaffold, said scaffold being configured to expand from a crimpedconfiguration to an expanded larger configuration; wherein at least oneof the circumferential rings follow a circumferential path about thecircumference of the scaffold and have at least one gap in said pathwhen the scaffold is in its expanded configuration and wherein adjacentrings are axially linked so that all portions of the scaffold remainconnected when the scaffold is in its expanded configuration.

403. A stent prosthesis as in clause 402, wherein the degradablematerial is polymeric or metallic material.

404. A stent prosthesis as in clause 370 or 402, wherein at least someof the axial links connect the struts and/or crown regions adjacent tothe gap to same or different ring.

405. A stent prosthesis as in clause 370, wherein the scaffold displaysa radial contraction and/or expansion displacement ranging from 0.1 mmto 0.5 mm when subjected to systolic/diastolic pressure cycling.

406. A stent prosthesis as in clause 370 or 402, wherein the axial linksconnect strut region to strut region, strut region to crown region,crown region to crown region, on adjacent rings.

407. A stent prosthesis comprising: a scaffold comprising anon-degradable material having a plurality of rings which define acircumference of the scaffold, said scaffold being configured to expandfrom a crimped configuration to an expanded larger configuration;wherein at least one of the circumferential rings follow acircumferential path about the circumference of the scaffold and have atleast one biodegradable segment in said path and wherein adjacent ringsare axially linked so that all portions of the scaffold remain connectedafter the biodegradable segments in the scaffold have degraded.

408. A stent prosthesis as in clause 407, wherein the biodegradablesegment is a bridging element.

409. A stent prosthesis as in clause 407, wherein each ring defines acircumference of the scaffold

410. A stent prosthesis as in clause 407, wherein at least some of thecircumferential rings follow a circumferential path about thecircumference of the scaffold and have at least one gap in said path ofeach ring.

411. A stent prosthesis as in clause 407, wherein the at least one ringwithout said biodegradable segment would have a gap or discontinuity insaid ring path.

412. A stent prosthesis as in clause 407, wherein the biodegradablesegments are configured to remain intact while the scaffold is expandedand to form gaps or discontinuities in the rings after the segments havedegraded.

413. A stent prosthesis as in clause 407, wherein the scaffold isexpanded in a vascular environment and to form gaps in the rings afterthe segments have degraded in the vascular environment.

414. A stent prosthesis as in clause 407, wherein the biodegradablesegments are configured to substantially degrade in a vascularenvironment over a time period in the range from 30 days to 2 years.

415. A stent prosthesis as in clause 407, wherein the biodegradablesegments are configured to substantially degrade in a vascularenvironment over a time period in the range from 30 days to 1 year.

416. A stent prosthesis as in clause 407, wherein the biodegradablesegments are configured to substantially degrade in a vascularenvironment over a time period in the range from 30 days to 9 months.

417. A stent prosthesis as in clause 407, wherein the biodegradablesegments in the circumferential rings are rotationally staggered.

418. A stent prosthesis as in clause 417, wherein the circumferentialrings are axially linked in a staggered pattern which is rotationallyoffset from the staggered gap pattern.

419. A stent prosthesis as in clause 407, wherein the circumferentialrings comprise serpentine rings.

420. A stent prosthesis as in clause 407, wherein the circumferentialrings comprise zig-zag rings.

421. A stent prosthesis as in clause 407, wherein the circumferentialrings comprise a closed cell design.

422. A stent prosthesis as in clause 407, wherein the non-degradablematerial comprises a metal or metal alloy.

423. A stent prosthesis as in clause 422, wherein the biodegradablesegments comprise a biodegradable polymer.

424. A stent prosthesis as in clause 407, wherein the circumferentialrings comprise a plurality of struts joined by crowns.

425. A stent prosthesis as in clause 423, wherein the biodegradablesegments are present in the crown regions.

426. A stent prosthesis as in clause 407, wherein the biodegradablesegments are present in the strut regions.

427. A stent prosthesis as in clause 407, wherein the biodegradablesegments span a crown and strut regions.

428. A stent prosthesis as in clause 407, wherein the biodegradablesegment bridges a gap or discontinuity in a strut region

429. A stent prosthesis as in clause 407, wherein the biodegradablesegment bridges a gap or discontinuity in a crown region.

430. A stent prosthesis as in clause 407, wherein the biodegradablesegment bridges a gap or discontinuity spanning at least one strutregion and a crown region.

431. A stent prosthesis as in clause 407, wherein the biodegradablesegment bridging a gap or discontinuity in a strut and/or crown regionoverlaps at least a portion of the non-degradable strut and/or crownregions.

432. A stent prosthesis as in clause 407, wherein the biodegradablesegment bridging a gap or discontinuity in a strut and/or crown regioncontains at least a portion of the non-degradable strut and/or crownregions.

433. A stent prosthesis as in clause 407, wherein the non-degradablestrut and/or crown region contains at least a portion of thebiodegradable segment.

434. A stent prosthesis as in clause 407, wherein the biodegradablesegment bridging a gap or discontinuity in a strut and/or crown regionforms a but joint with the non-degradable strut and/or crown regions.

435. A stent prosthesis as in clause 407, wherein the biodegradablesegment bridging a gap or discontinuity in a strut and/or crown regionforms a separation region with the non-degradable strut and/or crownregions.

436. A stent prosthesis as in clause 407, wherein the biodegradablesegment bridging a gap or discontinuity in a strut and/or crown regionforms a separation region with the non-degradable strut and/or crownregions, wherein the separation region comprises key and lock separationregion or key type separation region.

437. A stent prosthesis as in clause 407, wherein the scaffold displayscompliance between 1% to 5% in its expanded configuration without thebiodegradable segments when subjected to systolic/diastolic pressurecycling.

438. A stent prosthesis as in clause 407, wherein the scaffold displaysa compliance between 1% to 5% in its expanded configuration after thebiodegradable segments have degraded when subjected tosystolic/diastolic pressure cycling.

439. A stent prosthesis as in clause 407, wherein the scaffold displaysa compliance from 1.2% to 5%, often from 1.5% to 3%, in its expandedconfiguration with the biodegradable segments in place when subjected tosystolic/diastolic pressure cycling.

440. A stent prosthesis as in clause 407, wherein at least some of theaxial links connect the struts and/or crown regions adjacent to thebiodegradable segment on adjacent rings.

441. A stent prosthesis as in clause 407, wherein the scaffold displaysa radial contraction and/or expansion displacement ranging from 0.1 mmto 0.5 mm when subjected to systolic/diastolic pressure cycling.

442. A stent prosthesis as in clause 407, wherein the axial linksconnect strut region to strut region, strut region to crown region,crown region to crown region, on two adjacent rings.

443. A stent prosthesis as in clause 407, wherein the axial linksconnecting two adjacent crowns is formed by connecting the apex regionsof both crowns.

444. A stent prosthesis as in clause 407, wherein the axial links isformed by joining the two adjacent crown regions.

445. A stent prosthesis comprising: a scaffold comprising a degradablematerial having a plurality of rings which define a circumference of thescaffold, said scaffold being configured to expand from a crimpedconfiguration to an expanded larger configuration; wherein at least oneof the circumferential rings follow a circumferential path about thecircumference of the scaffold and have at least one biodegradablesegment in said path and wherein adjacent rings are axially linked sothat all portions of the scaffold remain connected upon deployment ofthe stent.

446. A stent prosthesis as in clause 445, wherein the degradablematerial comprises a polymer, metal, or metal alloy.

447. A stent prosthesis as in clause 445, wherein the degradablematerial degrades at a slower rate than the biodegradable segment

448. A stent prosthesis as in clause 445, wherein the degradablematerial degrades in a period ranging from 2 years to 10 years while thebiodegradable segment degrades in a period ranging from 30 days to 1year.

449. A stent prosthesis as in clause 407, wherein the stent in theexpanded configuration has sufficient strength to support a body lumen.

450. A stent as in clause 407, wherein the stent strength afterdegradation of the biodegradable segment decreases.

451. A stent prosthesis as in clause 407, wherein the stent patternafter degradation of the biodegradable segment remains substantially thesimilar.

452. A stent prosthesis as in clause 407, wherein the stent furthercomprises radiopaque markers.

453. A stent prosthesis as in clause 407, wherein the stent uncages thebody lumen after degradation of the biodegradable segment.

454. A stent prosthesis as in clause 407, wherein the stent is capableof vaso-dilation or vasoconstriction after deployment or afterdegradation of the biodegradable segment.

455. A stent prosthesis as in clause 407, wherein at least some ringshave at least two biodegradable segments each.

456. A stent prosthesis as in clause 407, wherein at least some ringshave at least three biodegradable segments each.

457. A stent prosthesis as in clause 407, wherein substantially allrings have at least one biodegradable segment

458. A stent prosthesis as in clause 407, wherein the biodegradablesegment length is substantially the same, longer, or shorter, than anadjacent strut and/or crown region.

459. A stent prosthesis as in clause 407, wherein the biodegradablesegment has a crown shape, a strut shape, a crown region shape, or astrut region shape.

460. A stent prosthesis as in clause 407, wherein the biodegradablesegment bridges a discontinuity or a gap, wherein the discontinuity orgap magnitude ranges from 0 to 2 mm

461. A stent prosthesis as in clause 407, wherein a coating covers atleast a portion of the biodegradable segment.

462. A stent prosthesis as in clause 407, wherein the stent comprises atleast one drug

463. A stent prosthesis as in clause 407, wherein a sleeve covers thebiodegradable segment and at least one portion of the non-degradablematerial.

464. A method of making an endovascular prosthesis, said methodcomprising: fabricating a first scaffold having a plurality of ringswhich define a circumference of the scaffold, wherein the plurality ofrings are formed from a non-degradable material; fabricating a secondscaffold having a plurality of rings which define a circumference of thescaffold, wherein the plurality of rings are formed from a biodegradablematerial and wherein the first and second scaffolds have identicalgeometries; forming gaps in portions of at least some of the rings ofthe first scaffold; cutting segments from the second scaffold, whereinthe segments are selected to fill in the gaps in the first scaffold; andsecuring the segments cut from the second scaffold into the gaps formedin the first scaffold.

465. A method of making an endovascular prosthesis as in clause 464,wherein the biodegradable material is selected to remain intact whilethe scaffold is expanded in a vascular environment and to form gaps inthe rings after the segments have degraded in the vascular environment.

466. A method of making an endovascular prosthesis as in clause 464,wherein the biodegradable material is selected to degrade in a vascularenvironment over a time period in the range from 30 days to 2 years.

467. A method of making an endovascular prosthesis as in clause 464,wherein the gaps in the circumferential rings of the first scaffold arerotationally staggered.

468. A method of making an endovascular prosthesis as in clause 467,wherein the circumferential rings in the first scaffold are axiallylinked in a staggered pattern which is rotationally offset from thestaggered gap pattern.

469. A method of making an endovascular prosthesis as in clause 464,wherein the circumferential rings in the first scaffold compriseserpentine rings.

470. A method of making an endovascular prosthesis as in clause 464,wherein the circumferential rings in the first scaffold comprise zig-zagrings.

471. A method of making an endovascular prosthesis as in clause 464,wherein the non-degradable material comprises a metal.

472. An endovascular prosthesis as in clause 472, wherein thebiodegradable material comprises a biodegradable polymer.

473. A method of making an endovascular prosthesis as in clause 464,wherein the circumferential rings comprise a plurality of struts joinedby crowns.

474. A method of making an endovascular prosthesis as in clause 473,wherein the gaps are present in the crowns.

475. A method of making an endovascular prosthesis as in clause 464,wherein the gaps are present in the struts.

476. A method of making an endovascular prosthesis as in clause 464,wherein the g span a crown and a strut.

477. A method of making an endovascular prosthesis as in clause 464,wherein the scaffold displays a compliance from 1% to 5%, often from1.5% to 3%, in its expanded configuration without the biodegradablesegments when subjected to systolic/diastolic pressure cycling.

478. An endovascular prosthesis as in clause 477, wherein the scaffolddisplays a compliance from 1.2% to 5% in its expanded configuration withthe biodegradable segments in place when subjected to systolic/diastolicpressure cycling.

Helical Stent

479. An endoluminal prosthesis comprising: a helical backbone having aplurality of struts joined by a plurality of crowns, wherein the helicalbackbone includes a multiplicity of adjacent turns and wherein at leastsome of the adjacent turns are attached to each other by a separationregion.

480. An endoluminal prosthesis as in clause 479, wherein the separationregions are disposed between immediately adjacent turns of the helicalbackbone.

481. An endoluminal prosthesis as in clause 480, wherein the separationregion are disposed between adjacent pairs of crowns.

482. An endoluminal prosthesis as in clause 480, wherein the separationregion are disposed on struts between a crown on one turn and strut onan adjacent turn.

483. An endoluminal prosthesis as in clause 480, wherein the separationregion are disposed on struts between adjacent pairs of struts.

484. An endoluminal prostheses as in clause 479, wherein the helicalbackbone has a serpentine arrangement.

485. An endoluminal prosthesis as in clause 479, wherein the helicalbackbone has a zig-zag arrangement.

486. An endoluminal prosthesis as in clause 479, wherein the helicalbackbone is formed from a bent wire.

487. An endoluminal prosthesis as in clause 479, wherein the helicalbackbone is formed from a patterned tube

488. An endoluminal prosthesis as in clause 479, wherein the separationregion comprises any of the separation regions described herein.

Overlapping Parallel Elements

489. An endoluminal prosthesis comprising: a scaffold havingcircumferential rings formed from a non-degradable material, saidscaffold being configured to expand from a crimped configuration to anexpanded configuration; wherein at least some of the circumferentialrings are formed from structural elements having divided regions whichoverlap and lie adjacent to each other when the scaffold is in itscrimped configuration.

490. An endoluminal prosthesis as in clause 489, wherein the adjacentregions which overlap and lie adjacent to each other are straight.

491. An endoluminal prosthesis as in clause 490, wherein the straightadjacent regions separate from each other when the scaffold is expandedto its expanded configuration.

492. An endoluminal prosthesis as in clause 490, wherein the straightadjacent regions are immobilized by a sleeve or an adhesive which willdegrade in a physiologic environment when the scaffold is in its crimpedconfiguration prior to deployment in the physiologic environment.

493. An endoluminal prosthesis as in clause 490, wherein the straightadjacent regions comprise a plurality of struts joined by crowns.

494. An endoluminal prosthesis as in clause 489, wherein the adjacentregions which overlap and lie adjacent to each other are curved.

495. An endoluminal prosthesis as in clause 489, wherein the curvedadjacent regions which overlap and lie adjacent to each other deformwhen the scaffold is expanded to its expanded configuration.

496. An endoluminal prosthesis as in clause 494, wherein the curvedadjacent regions are immobilized by a sleeve or an adhesive which willdegrade in a physiologic environment when the scaffold is in its crimpedconfiguration prior to deployment in the physiologic environment.

497. An endoluminal prosthesis as in clause 490, wherein the curvedadjacent regions comprise a plurality of crowns joined by struts.

Circumferentially Linked Closed Cells

498. An endoluminal prosthesis comprising: a scaffold havingcircumferential rings formed from a non-degradable material, saidscaffold being configured to expand from a crimped configuration to anexpanded configuration; wherein at least some of the circumferentialrings are formed as expandable closed cell structures and wherein saidexpandable closed cell structures are joined circumferentially; andwherein at least some of the circumferential rings have separationregions configured to form discontinuities in said circumferential ringsafter deployment in a luminal environment.

499. An endoluminal prosthesis as in clause 498, wherein the closedcells comprise quadrangles having opposed axial sides and opposedcircumferential sides, further comprising circumferential connectorswhich join axial sides of circumferentially adjacent closed cells,wherein the separation regions are in the circumferential connectors.

500. An endoluminal prosthesis as in clause 498, wherein at least someof the closed cells in axially adjacent circumferential rings are joinedby axial links.

501. An endoluminal prosthesis as in clause 498, wherein at least oneaxial link between each pair of axially adjacent circumferential ringsin the scaffold is configured to remain intact after implantation sothat all circumferential rings of the scaffold will remain joined afterdiscontinuities have formed in the separation regions in thecircumferential connectors after deployment in the luminal environment.

502. An endoluminal prosthesis as in clause 498, wherein thediscontinuities which form after implantation of said prosthesis in abody lumen allow the scaffold to display compliance from 1% to 5%, oftenfrom 1.2% to 3%, when subjected to systolic/diastolic pressure cyclingafter implantation in a blood vessel.

503. An endoluminal prosthesis as in clause 498, wherein the closedcells comprise closely packed quadrangles formed from common crossingmembers, wherein the separation regions are in the common crossingmembers.

504. An endoluminal prosthesis as in clause 498, wherein the separationregions are configured to degrade in response to implantation in theluminal environment.

505. An endoluminal prosthesis as in clause 504, wherein the separationregions are configured to fatigue and separate in response tosystolic/diastolic pressure cycling after implantation in a bloodvessel.

506. An endoluminal prosthesis as in clause 505, wherein the separationregions comprise notches or thinned regions in the circumferential ringswhich preferentially fatigue and break in response to applied energy.

507. An endoluminal prosthesis as in clause 498, wherein the separationregions are configured to fatigue in response to an externally appliedenergy source.

508. An endoluminal prosthesis as in clause 498, wherein the separationregions comprise a key and lock junction formed in the circumferentialconnectors, wherein said key and lock junctions are immobilized duringexpansion but configured to open in response to applied energy.

509. An endoluminal prosthesis as in clause 498, wherein the separationregions comprise a rivet or other fastener joining breaks in thecircumferential element and configured to open in response to appliedenergy.

510. An endoluminal prosthesis as in clause 498, wherein thenon-degradable material comprises a metal or a metal alloy.

511. A stent prosthesis comprising: a non-degradable patternedcircumferential scaffold including structural elements, said structuralelements having expansion regions configured to plastically deform asthe scaffold is radially expanded from a crimped configuration to afirst expanded configuration, wherein the structural elements areconfigured to allow the scaffold to passively expand to a second largerconfiguration after inward recoil from the first expanded configurationwherein the scaffold retains sufficient strength to support a body lumenfor at least an initial time period.

512. A stent prosthesis as in clause 511, wherein the time period rangesfrom 30 days to 9 months

513. A stent prosthesis as in clause 511, wherein the time period is atleast 30 days

514. A stent prosthesis as in clause 511, wherein the time period is ina range from after deployment day to 9 months.

515. A stent prosthesis as in clause 511, wherein the expansion regionscomprise separation regions.

516. A stent prosthesis as in clause 515, wherein the separation regionsare selected from a group consisting one or more of gaps, bridgeelements, controlled breaks, adjacent struts joined by sleeves, adjacentcrowns joined by sleeves, and/or key- and lock regions.

517. A stent prosthesis as in clause 511, wherein the expansion regionsare configured to weaken under physiologic cycling.

518. A stent prosthesis as in clause 517, wherein the expansion regionsconfigured to weaken under physiologic cycling are selected from a groupconsisting of hollowed out crown regions, hollowed out strut regions,and metals having predictable fatigue characteristics.

519. A stent prosthesis as in clause 518, wherein the expansion regionsconfigured to weaken under physiologic cycling comprise hollowed outcrown regions filled with a degradable material or, hollowed out strutregions filled with a degradable material.

520. A stent prosthesis as in clause 511, wherein the structuralelements are configured to allow the scaffold to passively expand to asecond larger configuration after systolic/diastolic cycling.

521 A stent prosthesis as in clause 520, wherein the systole/diastolecycling comprises a pressure difference of at least 40 mmHG at a ratefrom 2-30 Hz.

522. A stent prosthesis as in clause 511, wherein the patternedcircumferential scaffold comprises a plurality of axially joinedcircumferential rings.

523. A stent prosthesis as in clause 522, wherein the circumferentialrings comprise struts joined by crowns in a serpentine or zig-zagpattern.

524. A stent prosthesis as in clause 511, wherein the patternedcircumferential scaffold comprises a plurality of circumferentiallyjoined closed cells.

525. A stent prosthesis as in clause 511, wherein the second largerconfiguration is larger the first expanded configuration.

526. A stent prosthesis as in clause 511, wherein the scaffold isballoon deployable.

527. A stent prosthesis as in clause 511, wherein scaffold is deployableat body temperature.

528. A stent prosthesis as in clause 511, wherein the stent comprises aproximal segment, a mid-segment, and a distal segment, and wherein thestent expands to a second larger configuration in at least one segmentof the stent.

529. A stent prosthesis as in clause 511, wherein at least some of theexpansion regions comprise a non-degradable metal or metal alloy.

530. A stent prosthesis as in clause 511, wherein the stent furthercomprises radiopaque markers.

531. A stent prosthesis as in clause 511, wherein the stent comprises atleast one drug.

532. A stent prosthesis as in clause 511, wherein the stent comprises atleast one coating on at least one surface of the stent.

533. A stent prosthesis as in clause 511, wherein the scaffold has beenpatterned from a tubular body.

534. A stent prosthesis as in clause 511, wherein the scaffold comprisesa material which degrades in a luminal environment over a period in therange from 3 months to 3 years.

535. A stent prosthesis as in clause 534, wherein the degradablematerial comprises a polymeric material.

536. A stent prosthesis as in clause 534, wherein the degradablematerial comprises a metal or metal alloy.

537. A stent prosthesis as in clause 511, wherein the scaffold has atleast one segment configured to expand to a second larger configurationin response to introduction of a vaso-dilator to a patient after thestent has been expanded in a body lumen.

538. A stent prosthesis as in clause 537, wherein the scaffold isconfigured so that larger second configuration is substantiallymaintained after introduction of the vaso-dilator to the patient.

539. A stent prosthesis as in clause 511, wherein the second expandedconfiguration is larger than the first expanded configuration by adistance in a range from 0.05 mm to 1 mm.

540. A stent prosthesis comprising: a non-degradable patternedcircumferential scaffold including structural elements, said structuralelements having expansion regions configured to plastically deform asthe scaffold is radially expanded from a crimped configuration to afirst expanded configuration, wherein the scaffold is configured to havea radial strain in a range from 1.2% to 7% after the stent is expandedin a body and to retain sufficient strength to support the body lumen.

541. A stent prosthesis as in clause 540, wherein the scaffold isconfigured to have an inward recoil after deployment in a range from1.5% to 7%.

542. A stent prosthesis as in clause 540, wherein the scaffold isconfigured to have an initial radial strain after deployment of 1% orless before increasing to the radial strain in said range.

543. A stent prosthesis as in clause 540, wherein the radial strainreaches a value in said range within 2 months to 1 year afterdeployment.

544. A stent prosthesis as in clause 540, wherein a magnitude of theradial strain is in a range from 0.1 mm to 0.5 mm.

545. A stent prosthesis as in clause 540, wherein the patternedcircumferential scaffold comprises a plurality of axially joinedcircumferential rings.

546. A stent prosthesis as in clause 545, wherein the circumferentialrings comprise struts joined by crowns in a serpentine or zig-zagpattern.

547. A stent prosthesis as in clause 540, wherein the patternedcircumferential scaffold comprises a plurality of circumferentiallyjoined closed cells.

548. A stent prosthesis as in clause 540, wherein the second largerconfiguration is larger the first expanded configuration.

549. A stent prosthesis as in clause 540, wherein the scaffold isballoon deployable.

550. A stent prosthesis as in clause 540, wherein scaffold is deployableat body temperature.

551. A stent prosthesis as in clause 540, wherein the stent comprises aproximal segment, a mid-segment, and a distal segment, and wherein thestent expands to a second larger configuration in at least one segmentof the stent.

552. A stent prosthesis as in clause 540, wherein at least some of theexpansion regions comprise a non-degradable metal or metal alloy.

553. A stent prosthesis as in clause 540, wherein the stent furthercomprises radiopaque markers.

554. A stent prosthesis as in clause 540, wherein the stent comprises atleast one drug.

555. A stent prosthesis as in clause 540, wherein the stent comprises atleast one coating on at least one surface of the stent.

556. A stent prosthesis as in clause 540, wherein the scaffold has beenpatterned from a tubular body.

557. A stent prosthesis as in clause 540, wherein the scaffold comprisesa material which degrades in a luminal environment over a period in therange from 3 months to 3 years.

558. A stent prosthesis as in clause 557, wherein the degradablematerial comprises a polymeric material.

559. A stent prosthesis as in clause 557, wherein the degradablematerial comprises a metal or metal alloy.

560. A stent prosthesis as in clause 540, wherein the scaffold has atleast one segment configured to expand to a second larger configurationin response to introduction of a vaso-dilator to a patient after thestent has been expanded in a body lumen.

561. A stent prosthesis as in clause 560, wherein the scaffold isconfigured so that larger second configuration is substantiallymaintained after introduction of the vaso-dilator to the patient.

562. A stent prosthesis as in clause 540, wherein the second expandedconfiguration is larger than the first expanded configuration by adistance in a range from 0.05 mm to 1 mm.

563. A stent prosthesis comprising: a non-degradable patternedcircumferential scaffold including structural elements, said structuralelements having expansion regions configured to plastically deform asthe scaffold is radially expanded from a crimped configuration to afirst expanded configuration, wherein the scaffold in the deployedconfiguration has sufficient strength to support a body lumen andwherein the scaffold is configured to allow a stented segment in thebody lumen to vaso-dilate and/or vaso-constrict in the presence of avaso-dilator and/or vaso-constrictor agent in the body lumen.

564. A stent prosthesis as in clause 563, wherein the stented segment ofthe body lumen vaso-dilates in a range from 0.05 mm to 0.5 mm.

565. A stent prosthesis as in clause 563, wherein the stented segment ofthe body lumen vaso-dilates in a range from 0.1 mm to 0.3 mm.

566. A stent prosthesis as in clause 563, wherein the patternedcircumferential scaffold comprises a plurality of axially joinedcircumferential rings.

567. A stent prosthesis as in clause 565, wherein the circumferentialrings comprise struts joined by crowns in a serpentine or zig-zagpattern.

568. A stent prosthesis as in clause 563, wherein the patternedcircumferential scaffold comprises a plurality of circumferentiallyjoined closed cells.

569. A stent prosthesis as in clause 563, wherein the second largerconfiguration is larger the first expanded configuration.

570. A stent prosthesis as in clause 563, wherein the scaffold isballoon deployable.

571. A stent prosthesis as in clause 563, wherein scaffold is deployableat body temperature.

572. A stent prosthesis as in clause 563, wherein the stent comprises aproximal segment, a mid-segment, and a distal segment, and wherein thestent expands to a second larger configuration in at least one segmentof the stent.

573. A stent prosthesis as in clause 563, wherein at least some of theexpansion regions comprise a non-degradable metal or metal alloy.

574. A stent prosthesis as in clause 563, wherein the stent furthercomprises radiopaque markers.

575. A stent prosthesis as in clause 563, wherein the stent comprises atleast one drug.

576. A stent prosthesis as in clause 563, wherein the stent comprises atleast one coating on at least one surface of the stent.

577. A stent prosthesis as in clause 563, wherein the scaffold has beenpatterned from a tubular body.

578. A stent prosthesis as in clause 563, wherein the scaffold comprisesa material which degrades in a luminal environment over a period in therange from 3 months to 3 years.

579. A stent prosthesis as in clause 578, wherein the degradablematerial comprises a polymeric material.

580. A stent prosthesis as in clause 578, wherein the degradablematerial comprises a metal or metal alloy.

581. A stent prosthesis as in clause 563, wherein the scaffold has atleast one segment configured to expand to a second larger configurationin response to introduction of a vaso-dilator to a patient after thestent has been expanded in a body lumen.

582. A stent prosthesis as in clause 581, wherein the scaffold isconfigured so that larger second configuration is substantiallymaintained after introduction of the vaso-dilator to the patient.

583. A stent prosthesis as in clause 563, wherein the second expandedconfiguration is larger than the first expanded configuration by adistance in a range from 0.05 mm to 1 mm.

584. A stent prosthesis comprising: a non-degradable patternedcircumferential scaffold including structural elements, said structuralelements having expansion regions configured to plastically deform asthe scaffold is radially expanded from a crimped configuration to afirst expanded configuration, wherein the scaffold in the deployedconfiguration has sufficient strength to support a body lumen andwherein the scaffold is configured to contract and/or expand afterdeployment in a body lumen under physiologic conditions.

585. A stent prosthesis as in clause 584, wherein expansion and/orcontraction occurs passively.

586. A stent prosthesis as in clause 584, wherein expansion and/orcontraction occurs in response to vaso-dilation and/orvaso-constriction.

587. A stent prosthesis as in clause 584, wherein expansion and/orcontraction occurs under physiologic pulsation.

588. A stent prosthesis as in clause 584, wherein expansion and/orcontraction has magnitude in a range from 0.05 mm to 0.5 mm from adeployed diameter or mean diameter of the body lumen.

589. A stent prosthesis as in clause 584, wherein expansion and/orcontraction has magnitude in the range from 0.1 mm to 0.4 mm from adeployed diameter or mean diameter of the body lumen.

590. A stent prosthesis as in clause 584, wherein the scaffold has aradial compliance in a range from 1.2% and 5%.

591. A stent prosthesis as in clause 584, wherein the scaffold has aradial compliance in a range from 1.5% to 5%.

592. A stent prosthesis comprising: a non-degradable patternedcircumferential scaffold including structural elements, said structuralelements having expansion regions configured to plastically deform asthe scaffold is radially expanded from a crimped configuration to afirst expanded configuration, wherein the scaffold has sufficientstrength to support a body lumen, and wherein the number, location, andpattern of the separation regions are configured to control stresses onthe stent structural elements, wherein the stent structural elements donot fracture after deployment under physiologic conditions.

593. A stent prosthesis comprising: a non-degradable patternedcircumferential scaffold including a plurality of axially joinedcircumferential rings, where at least some of the circumferential ringscomprise struts joined by crowns and have at least one separation regionwhich forms a discontinuity in said ring after deployment, wherein thescaffold is configured to withstand 10 million fatigue cycles underphysiologic conditions without fracture.

594. A stent prosthesis comprising: a non-degradable patternedcircumferential scaffold including a plurality of axially joinedcircumferential rings, where at least some of the circumferential ringscomprise struts joined by crowns and have at least one separation regionwhich forms a discontinuity in said ring after deployment, wherein afterdiscontinuities are formed, substantially all resulting segments of thering remain axially joined.

595. A stent prosthesis comprising: a non-degradable patternedcircumferential scaffold including a plurality of axially joinedcircumferential rings, where at least some of the circumferential ringscomprise struts joined by crowns and have at least some separationregions which form discontinuities in said rings after deployment,wherein the scaffold in the deployed configuration has sufficientstrength to support a body lumen, and wherein the stent strengthdecreases after the at least some separation regions formdiscontinuities.

596. A stent prosthesis as in clause 595, wherein the stent strengthdecrease ranges from 15% to 75% in a period ranging from 30 days to 9months.

597. A stent prosthesis as in clause 595, wherein the stent has inwardrecoil after deployment ranging from 1% to 10%.

598. A stent prosthesis as in clause 595, wherein the stent after inwardrecoil further expands after formation of discontinuities.

599. A stent prosthesis as in clause 595, wherein the stent afterdeployment has radial strain ranging from 1.2% to 5%.

600. A stent prosthesis as in clause 595, wherein the stent afterdeployment has radial strain ranging from 0.1% to 1%, and wherein theradial strain increases after formation of discontinuities to a rangefrom 1.2% to 5%.

601. A stent prosthesis as in clause 595, wherein the stent strengthafter the at least some separation regions form discontinuities isinsufficient to support a body lumen.

602. A stent prosthesis as in clause 595, wherein the stent after the atleast some separation regions form discontinuities is held in place bythe lumen tissue.

603. A stent scaffold comprising: a backbone; a plurality ofcircumferential rings distributed along the length of the backbone;wherein at least some of the circumferential rings have gaps and whereinat least some of the axially successive gaps are rotationally staggeredto enhance uniformity of the circumferential strength of the stentscaffold.

604. A stent prosthesis as in clause 1600, wherein the backbone has anaxially continuous structure which extend over the entire length of thestent scaffold.

605. A stent prosthesis as in clause 1600, wherein the backbonecomprises a plurality of segments which are rotationally staggered overthe length of the stent scaffold.

Stent Scaffolds with Circumferential Displacement Regions

606. A stent prosthesis comprising: a scaffold having circumferentialrings patterned from a polymeric or metallic material, said scaffoldbeing configured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential rings haveat least one circumferential displacement region which allows thecircumferential ring to circumferentially expand and contract in aphysiologic luminal environment.

607. A stent prosthesis as in clause 606, wherein the at least onecircumferential displacement region allows the circumferential ring tocircumferentially expand and contract in response to asystolic/diastolic rhythm in an arterial lumen.

608. A stent prosthesis as in clause 607, wherein the scaffold includesa plurality of the circumferential rings coupled together along an axis,where at least some of the circumferential rings comprise struts joinedby crowns and at least some of the struts or crowns have discontinuitiesthat allow the circumferential ring(s) to circumferentially expand andcontract in response to a systolic/diastolic rhythm in the arteriallumen.

609. A stent prosthesis as in clause 608, wherein the discontinuitiesthat allow the circumferential ring(s) to circumferentially expand andcontract in response to a systolic/diastolic rhythm in the arteriallumen comprise gaps between opposed segments of a strut or a crown.

610. A stent prosthesis as in clause 609, wherein the gaps are definedby between two opposed segments of a strut and comprise a femalecoupling element that comprises a pair of opposed constraining walls onone strut segment and a male coupling element disposed on an opposedstrut segment and located between the pair of opposed constraining wallson the one strut segment, wherein the male element is free to movecircumferentially between the opposed walls of the circumferential ringto circumferentially expand and contract.

611. A stent prosthesis as in clause 610, wherein the gaps defined bybetween two opposed segments are open.

612. A stent prosthesis as in clause 610, wherein the gaps defined bybetween two opposed segments are filled with an elastomeric cushionmaterial which dampens the circumferential movement of the male elementbetween the opposed walls of the circumferential ring.

613. A stent prosthesis as in clause 609, wherein the gaps are definedbetween spaced-apart ends of two opposed segments of a strut.

614. A stent prosthesis as in clause 613, wherein the gaps between thespaced-apart ends of two opposed segments of a strut are filled with anelastomeric cushion material which dampens the relative circumferentialmovement of the opposed segments.

615. A stent prosthesis as in clause 613, wherein the gaps defined bybetween two opposed segments are open.

616. A stent prosthesis as in clause 609, wherein the gaps are definedby between two opposed segments of a strut and comprise a couplingelement having a channel that comprises a pair of opposed constrainingwalls and a bottom surface on one strut segment and a male couplingelement disposed on an opposed strut segment and located between thepair of opposed constraining walls and over the bottom surface on theone strut segment, wherein the male element is free to movecircumferentially between the opposed walls of the circumferential ringto circumferentially expand and contract.

617. A stent prosthesis as in clause 616, wherein the gaps between thespaced-apart ends of two opposed segments of a strut are filled with anelastomeric cushion material which dampens the relative circumferentialmovement of the opposed segments.

618. A stent prosthesis as in clause 615, wherein the gaps defined bybetween two opposed segments are open.

619. A stent prosthesis as in clause 609, wherein the gaps are definedby between two opposed segments of a strut and comprise a couplingelement having a pin pivotally joining the two opposed segments.

Fabrication of Stents from Flat Panels

620. A method of fabricating a stent prosthesis, said method comprising:patterning two or more panels, each panel including a plurality ofpartial ring structures and each partial ring structure terminating intwo or more attachment ends; forming the two or more panel structuresinto a cylindrical assembly with each attachment end on one panel beingadjacent to an attachment structure on another panel; and joining theend structures together to form a cylindrical scaffold having aplurality of continuous ring structures about a circumference thereof.

621. A method as in clause 620, wherein at least some of the partialring structures comprise struts joined by crowns.

622. A method as in clause 620 wherein the attachment ends are patternedas male and female elements configured to mate with a gap therebetweento allow the circumferential scaffold to circumferentially expand andcontract in a physiologic luminal environment.

623. A method as in clause 622 further comprising filling the gaps withan elastomeric material to provide an elastic attachment between theattachment ends.

624. A method as in clause 620, wherein forming comprises bending thepanels over a cylindrical mandrel.

625. A method as in clause 620, wherein joining the end structurestogether comprises applying an elastomeric material between adjacent endstructures.

626. A method as in clause 620, wherein joining the end structurestogether comprises applying an elastomeric material over the adjacentend structures.

627. A method as in clause 620, wherein joining the end structurestogether comprises applying an elastomeric sleeve over the adjacent endstructures.

Radially Oriented Tab Designs

628. A stent prosthesis comprising: a scaffold having circumferentialrings patterned from a polymeric or metallic material, said scaffoldbeing configured to expand from a crimped configuration to an expandedconfiguration; wherein at least some of the circumferential rings arejoined by axial links and wherein at least some of the axial links arejoined to an adjacent circumferential ring by a circumferentialdisplacement region which allows the circumferential ring tocircumferentially expand and contract in a physiologic luminalenvironment.

629. A stent prosthesis as in clause 628, wherein the at least onecircumferential displacement regions allow the circumferential ring tocircumferentially expand and contract in response to asystolic/diastolic rhythm in an arterial lumen.

630. A stent prosthesis as in clause 629, wherein the scaffold includesa plurality of circumferential rings coupled together along an axis bythe axial links and wherein at least some of the circumferential ringscomprise struts joined by crowns and a strut on the adjacentcircumferential ring terminates in the circumferential displacementregion which is joined to the axial link.

631. A stent prosthesis as in clause 630, wherein the discontinuitiesthat allow the circumferential ring(s) to circumferentially expand andcontract in response to a systolic/diastolic rhythm in the arteriallumen comprise gaps between opposed segments of a strut or a crown.

632. A stent prosthesis as in clause 630, wherein the circumferentialdisplacement regions comprise a male segment and a female couplingelement.

633. A stent prosthesis as in clause 632, wherein the male segment is ata terminal end of a strut and the female coupling element is on theaxial link.

634. A stent prosthesis as in clause 632, wherein the female segment isat a terminal end of a strut and the male coupling element is on theaxial link.

635. A stent prosthesis as in clause 632, wherein the male element isfree to move circumferentially between opposed walls of the femalecoupling member to circumferentially expand and contract the stentprosthesis.

636. A stent prosthesis as in clause 632, wherein the male segment and afemale coupling element are separated by gap.

637. A stent prosthesis as in clause 611, wherein the gaps are filledwith an elastomeric cushion material which dampens the circumferentialmovement of the male element between the opposed walls of thecircumferential ring.

Valve Clauses

638. A stent prosthesis for valve repair or replacement comprising: astent prosthesis comprising patterned structural elements, said stentbeing expandable from a crimped configuration to an expanded largerconfiguration and having sufficient strength to support a body annulusin the expanded configurations; wherein at least one valve is coupled tothe stent prosthesis allowing for blood to flow though the valvesubstantially in one direction during the cardiac cycle; and wherein atleast one segment of the stent comprises one or more uncaging elementsto allow said segment to have larger displacement than an adjacent stentsegment in the expanded stent configuration under physiologicalcondition.

639. A stent prosthesis as in clause 638, wherein the displacementcomprises one or more of radial direction, circumferential direction,longitudinal direction, direction to bias the valve to close, directionto accommodate the annulus compliance, or combination thereof.

640. A stent as in clause 638, wherein the uncaging elements comprisesone or more of separation regions, bridging element, reinforcementelements, junctions, joints, hinges, gaps, discontinuities.

641. A stent prosthesis as in clause 638, wherein the strength in theuncaging elements is lower than the adjacent segment

642. A stent prosthesis as in clause 638, wherein the stent is balloonexpandable or self-expandable prosthesis

643. A stent prosthesis as in clause 638, wherein the stent furthercomprises at least one skirt on at least one surface of the stentprosthesis, and wherein the skirt accommodates the displacement

644. A stent prosthesis as in clause 638, wherein the stent is formedfrom a tube, a braided one or more wires, or from a wire, or combinationthereof.

645. A stent prosthesis as in clause 638, wherein the stent prosthesispattern is a closed cell pattern, and open cell pattern, or acombination thereof.

646. A stent prosthesis as in clause 638, wherein the stent is formedfrom a non-degradable metallic or polymeric material.

647. A stent prosthesis as in clause 638, wherein the stent is formedfrom a degradable metallic or polymeric material.

648. A stent prosthesis as in clause 638, wherein at least some of thestructural elements contain uncaging elements.

649. A stent prosthesis as in clause 638, wherein the uncaging elementsare adjacent to at least one coupled region of the valve to the stent.

650. A stent prosthesis as in clause 638, wherein the radial strain ofthe at least one segment is larger than the adjacent segment by amagnitude ranging from 0.1% to 20%, preferably ranging from 0.2% to 10%,more preferably ranging from 0.5% to 10%.

651. A stent prosthesis as in clause 638, wherein the at least onesegment has radial strain ranging from 0.3% to 20%, preferably rangingfrom 0.5% to 10%, more preferably ranging 1% to 10%.

652. A stent prosthesis as in clause 638, wherein the pattern of theuncaging elements conforms to the pattern of the annulus.

653. A stent prosthesis as in clause 638, wherein the at least onesegment has radial contraction and/or expansion in the expanded stentconfiguration larger than the adjacent segment.

654. A stent prosthesis as in clause 638, wherein the at least onesegment has radial contraction and/or expansion in the expanded stentconfiguration larger than the adjacent segment by at least 10%,preferably larger by at least 20%.

655. A stent prosthesis as in clause 638, wherein the patternedstructural elements comprises one or more of: one or more wires, braidedone or more wires, struts, crowns, circumferential links, axial links.

656. A stent prosthesis as in clause 638, wherein the uncaging elementsallow for larger displacement after expansion of the stent prosthesis.

657. A stent prosthesis as in clause 638, wherein the uncaging elementsallow for the larger displacements in a period ranging from 3 months to3 years after deployment (or expansion) in a body annulus.

658. A stent prosthesis for vale repair or replacement comprising: astent prosthesis comprising patterned structural elements, said stentbeing self-expandable from a crimped configuration to an expanded largerconfiguration, and having sufficient strength to support a body annulusin the expanded configurations, and wherein at least one valve iscoupled to the stent prosthesis allowing for blood to flow though thevalve substantially in one direction during the cardiac cycle, andwherein at least one segment of the stent comprises one or more uncagingelements to reduce the strength of said segment compared to an adjacentstent segment in the expanded stent configuration under physiologicalcondition.

659. A stent prosthesis as in clause 658, wherein the at least onesegment is the segment nearest to the ventricle.

660. A stent prosthesis as in clause 658, wherein the at least onesegment uncaging minimizes damage to the pacing node or coronary sinus.

661. A stent prosthesis as in clause 658, wherein the at least onesegment has lower strength by at least 10%.

662. A stent prosthesis as in clause 658, wherein the at least onesegment has lower strength than the adjacent segment in the expandedconfiguration and less than the maximum expanded configuration of thestent.

663. An implant for valve repair or replacement comprising: structuralelements comprising one or more elements each having one or more oflength, width, and thickness, said structural element is positionedadjacent to a valve annulus and affixed in place, and wherein thestructural element is coupled to a stent containing a valve deployed inthe annulus of the valve; wherein at least one segment of the structuralelement is configured to have uncaging elements to allow said segment tohave a displacement larger than an adjacent segment of the structuralelement.

664. An implant as in clause 663, wherein at least one stent segmentcontracts and/or expands during the displacement of the at least onesegment

665. An implant as in clause 663, wherein the valve closes or opensduring the displacement of the at least one segment.

666. An implant as in clause 663, wherein the structural elementcontours at least part of the perimeter of the valve annulus

667. An implant as in clause 663, wherein the structural element ispositioned adjacent to the annulus, superior to the annulus, or inferiorto the annulus.

668. An implant as in clause 663, wherein the structural elementsubstantially circles the annulus.

669. An implant as in clause 663, wherein the structural elementcomprises one or more structural elements.

670. An implant for valve repair or replacement comprising: structuralelement comprising one or more elements each having one or more oflength, width, and thickness, said structural element is positionedadjacent to a valve annulus and affixed in place, and wherein thestructural element is coupled to an implanted valve; wherein at leastone segment of the structural element is configured to have uncagingelements to allow said segment to have a displacement larger than anadjacent segment of the structural element.

671. An implant as in clause 670, wherein at least one valve segmentradially contracts and/or expands during the displacement of the atleast one segment

672. A stent prosthesis as in clause 670, wherein the valve closesand/or opens during the displacement of the at least one segment.

673. A stent prosthesis as in clause 670, wherein the structural elementcontours at least part of the perimeter of the valve annulus

674. A stent prosthesis as in clause 670, wherein the structural elementis positioned adjacent to the annulus, superior to the annulus, orinferior to the annulus.

Stent Prosthesis Clauses

675. A stent prosthesis comprising: a non-degradable metal or metalalloy material, said material patterned into a substantially cylindricalstructure capable of being expandable from a crimped configuration to anexpanded larger configuration and having sufficient strength in theexpanded configuration to support a body lumen; wherein said structurecomprises structural elements comprising a plurality of circumferentialrings, wherein each ring is connected to an adjacent ring via one ormore axial links, and/or via connecting at least one structural elementregion on said each ring to a structural element region on said adjacentring; wherein each ring comprises struts joined by crowns; wherein atleast some circumferential rings have one or more separation regionsalong the circumferential path of said rings, and wherein saidseparation regions form discontinuities after expansion; and whereinsaid stent and/or said at least some rings after formation of saiddiscontinuities exhibit one or more of the following: a radial strainranging between 1% and 5%, a radial displacement ranging from 0.05 mm to1.5 mm, further expand to a larger expanded configuration after inwardrecoil from said expanded configuration, vaso-dilatation and/orvaso-constriction in the magnitude ranging from 0.05 mm to 0.5 mm,reduction in strength after stent expansion, uncaging circumferentially,or reduction in hoop stresses, under physiologic conditions, and whereinthe at least some rings having one or more separation regions remainsubstantially connected to adjacent rings after expansion.

676. A stent prosthesis as in clause 675, wherein the at least somerings are connected to adjacent rings via two or more axial links,and/or via connecting two or more structural element regions on the atleast some rings to two or more structural element regions on saidadjacent rings, and wherein the at least some rings remain substantiallyconnected to said adjacent rings after expansion.

677. A stent prosthesis as in clause 675, wherein the at least somerings are connected to adjacent rings via three or more axial links,and/or via connecting three or more structural element regions on the atleast some rings to three or more structural element regions on saidadjacent rings, and wherein the at least some rings remain substantiallyconnected to said adjacent rings after expansion.

678. A stent prosthesis as in clause 675, wherein each ring remainssubstantially connected to an adjacent ring after expansion.

679. A stent prosthesis as in clause 675, wherein at least someseparation regions form discontinuities after expansion ranging from 30days to 9 months.

680. A stent prosthesis as in clause 675, wherein at least someseparation regions form discontinuities after expansion ranging from 1day to 30 days.

681. A stent prosthesis as in clause 675, wherein the radial strainranges from 1.5%-5% under physiologic conditions where the unconstrainedlumen or tube have a radial strain of approximately 5%.

682. A stent prosthesis as in clause 675, wherein the radialdisplacement ranges from 0.1 mm to 0.3 mm.

683. A stent prosthesis as in clause 675, wherein the vaso-dilatationand/or vaso-constriction magnitude ranges from 0.07 mm to 0.3 mm

684. A stent prosthesis as in clause 675, wherein the reduction instrength ranges from 10% to 90% of the initial expanded configurationstrength.

685. A stent prosthesis as in clause 675, wherein the reduction in hoopstresses after expanses ranges from 10% to 90% of the initial expandedconfiguration hoop stresses.

686. A stent prosthesis as in clause 675, wherein substantially allrings have one or more separation regions.

687. A stent prosthesis as in clause 675, wherein at least someseparation regions form discontinuities during expansion.

688. A stent prosthesis as in clause 675, wherein at least someseparation regions form discontinuities before expansion.

689. A stent prosthesis as in clause 675, wherein at least someseparation regions are held together during deployment (expansion) fromthe crimped configuration to the expanded larger configuration.

690. A stent prosthesis as in clause 675, wherein at least someseparation regions are held together during deployment (expansion) fromthe crimped configuration to the expanded larger. configuration andwherein the separation regions are held together by a jointconfiguration, key and lock type configuration, polymer material,adhesive material, solder, fusing structural elements, or combinationthereof.

691. A stent prosthesis as in clause 675, wherein substantially all therings remain connected to adjacent rings after expansion.

692. A stent prosthesis as in clause 675, wherein the stent issubstantially cylindrical.

693. A stent prosthesis as in clause 675, wherein each ring extendsaround a circumference of the stent forming an angle with thelongitudinal axis of the stent.

694. A stent prosthesis as in clause 675, wherein the stent prosthesisis plastically deformed when expanded from a crimped configuration to anexpanded larger configuration.

695. A stent prosthesis as in clause 675, wherein the stent comprises atleast one polymer coating on at least one surface of the stent.

696. A stent prosthesis as in clause 675, wherein the stent comprises atleast one drug on at least one surface of the stent.

697. A stent prosthesis as in clause 675, wherein the stent is balloondeployable.

698. A stent prosthesis as in clause 675, wherein the stent is formedfrom a tube then patterned, patterned from one or more wires, or formedfrom a rolled up patterned sheet.

699. A stent prosthesis as in clause 675, wherein the stent issubstantially cylindrical.

700. A stent prosthesis as in clause 675, wherein the non-degradablemetal or metal alloy comprises one of: stainless steel, cobalt chrome,platinum iridium

701. A stent prosthesis as in clause 675, wherein the at least somerings after formation of said discontinuities separates into at leasttwo strips along the length of the stent prosthesis, while the at leastsome rings remain substantially connected to adjacent rings.

702. A stent prosthesis as in clause 675, wherein each ring has one ormore separation regions, and wherein the stent after formation of saiddiscontinuities separates into at least two strips along the length ofthe stent prosthesis, while the rings remain connected to adjacentrings.

703. A stent prosthesis as in clause 675, wherein the initial radialstrain of the stent after expansion to 4 mm ranges from 0.1% to 1% andincreases to a range from 1.1% to 3.5% within a period ranging from 1day to 9 months after expansion, under physiologic condition, saidexpansion within a lumen having unconstrained radial strain ranging from4% to 5%.

704. A stent prosthesis as in clause 675, wherein the initial radialstrain of the stent after expansion to 4 mm ranges from 0.1% to 1% andincreases to a range from 1.1% to 3.5% within a period ranging from 1day to 9 months after expansion, under physiologic condition, saidexpansion within a lumen having unconstrained radial strain ranging from4% to 5%, and wherein the stent maintains a structure in the increasedradial strain configuration preventing it from matching theunconstrained radial strain of the lumen.

705. A stent prosthesis as in clause 675, wherein the stent prosthesishas an initial radial strain after expansion and wherein the radialstrain changes under physiologic conditions

706. A stent prosthesis as in clause 675, wherein the stent prosthesishas an initial radial strain after expansion and wherein the stentradial strain increases under physiologic conditions

707. A stent prosthesis as in clause 675, wherein the stent prosthesishas an initial radial strain after expansion and wherein the radialstrain of the stent substantially increases under physiologic conditionsin a period ranging from 1 day to 1 year.

708. A stent prosthesis as in clause 675, wherein the stent has aninitial radial strain after expansion and wherein the radial expansionincreases by a factor ranging from 1.2 to 15 times the initial radialstrain after formation of discontinuities.

709. A stent prosthesis as in clause 675, wherein the stent has aninitial radial strain after expansion and wherein the radial expansionincreases by a factor ranging from 1.5 to 15 times the initial radialstrain after formation of discontinuities.

710. A stent prosthesis as in clause 675, wherein the stent has aninitial radial strain after expansion and wherein the radial expansionincreases by a factor ranging from 1.7 to 15 times the initial radialstrain after formation of discontinuities.

711. A stent prosthesis as in clause 675, wherein the radial strain ofthe stent after expansion ranges from 0.15% to 0.75% of the unstentedlumen radial strain adjacent to the stented segment.

712. A stent prosthesis as in clause 675, wherein the radial strain ofthe stent after expansion ranges from 0.25% to 0.75% of the unstentedlumen radial strain adjacent to the stented segment.

713. A stent prosthesis as in clause 675, wherein the radial strain ofthe stent after expansion ranges from 0.30% to 0.75% of the unstentedlumen radial strain adjacent to the stented segment, and wherein thestent retains a patterned structure after formation of discontinuities.

714. A stent prosthesis as in clause 675, wherein the stent has aninitial strength after expansion and wherein the strength decreases byat least 25% of said initial strength after formation of saiddiscontinuities.

715. A stent prosthesis as in clause 675, wherein the stent has aninitial strength after expansion and wherein the strength decreases by25% to 75% of said initial strength after formation of at least somediscontinuities.

716. A stent prosthesis as in clause 675, wherein the stent has aninitial strength after expansion and wherein the strength decreases by50% to 85% of said initial strength after formation of at least somediscontinuities.

717. A stent prosthesis as in clause 675, wherein the stent has aninitial strength after expansion and wherein the strength diminishesafter formation of at least some discontinuities or substantially alldiscontinuities, and wherein the stent prosthesis retains asubstantially interconnected 1 to 5 patterned strips along the length tosupport a body lumen.

718. A stent prosthesis as in clause 675, wherein the separation regionsare positioned along the circumferential path of a circumferentialstructural element, and wherein the number of separation regions aresufficient to forma discontinuity in said circumferential structuralelement.

719. A stent prosthesis as in clause 675, wherein at least some ringshave no more than one separation region for every one crowns connectingtwo struts.

720. A stent prosthesis as in clause 675, wherein at least some ringshave no more than one separation region for every two crowns connectinga total of three struts.

721. A stent prosthesis as in clause 675, wherein at least some ringshave no more than one separation region per ring segment wherein thering segment comprises one strut connected to two crowns.

722. A stent prosthesis as in clause 675, wherein at least some ringshave no more than one separation region per a ring segment wherein thering segment comprises one strut connected two crowns, and wherein theseparation region is located in the substantially non-deformable strutregion.

723. A stent prosthesis as in clause 675, wherein at least some ringshave no more than one separation region per a ring segment wherein thering segment comprises three crowns connecting three struts, and whereinthe separation region is located on the substantially non-deformableregion of any of the struts.

724. A stent prosthesis as in clause 675, wherein at least some ringshave no more than one separation region per a ring segment wherein thering segment comprises three crowns connecting four struts, and whereinthe separation region is located on the substantially non-deformableregion of any of the struts.

725. A stent as in clause 675, wherein the radial strain of the bodylumen is about 5%.

726. A stent as in clause 675, wherein the radial strain of the bodylumen ranges from 3.5%-10%.

727. A stent prosthesis as in clause 675, wherein the at least somerings have no more than 4 separation regions per at least some rings.

728. A stent prosthesis as in clause 675, wherein the at least somerings have no more than 5 separation regions per at least some rings.

729. A stent prosthesis as in clause 675, wherein the at least somerings have no more than 6 separation regions per ring

730. A stent prosthesis as in clause 675, wherein the at least somerings have no more than three separation regions per ring.

731. A stent prosthesis as in clause 675, wherein the axial links rangefrom 1 to 4 links, for a stent pattern having circumferential ringscomprising crowns wherein the number of crowns ranges from 3 crowns to 9crowns.

732. A stent prosthesis as in clause 675, wherein the links connectingat least some rings are spaced every crown, every other crown, every twocrown, or every three crowns.

733. A stent prosthesis as in clause 675, wherein the location of atleast some separation regions on at least some circumferential rings arelocated on struts or crowns adjacent to a link.

734. A stent prosthesis as in clause 675, wherein the location of atleast some separation regions on at least some circumferential rings arelocated on struts or crowns not adjacent to a link.

735. A stent prosthesis as in clause 675, wherein the structural elementregions comprises crown and/or strut regions.

736. A stent prosthesis as in clause 675, wherein the separation regionsbreak the circumferential structural integrity of the at least somerings or stent.

737. A stent prosthesis as in clause 675, wherein the stent has aninitial stiffness in the expanded configuration and wherein thestiffness decreases by a magnitude ranging from 10% to 100% within aperiod ranging from 1 day to 9 months after expansion.

738. A stent prosthesis as in clause 675, wherein the stent has aninitial strength in the expanded configuration and wherein the strengthdecreases by a magnitude ranging from 10% to 100% within a periodranging from 1 day to 9 months after expansion.

739. A stent prosthesis as in clause 675, wherein the stent has initialstrength after expansion and wherein the strength decreases afterformation of at least some discontinuities, and wherein the decreasedstent strength is sufficient to substantially maintain open the bodylumen.

740. A stent prosthesis as in clause 675, wherein the stent has initialstrength after expansion and wherein the strength decreases afterformation of at least some discontinuities, and wherein the decreasedstent strength is sufficient to support the body lumen.

741. A stent prosthesis as in clause 675, wherein the stent has initialstrength after expansion and wherein the strength decreases afterformation of at least some discontinuities, and wherein the stentretains a patterned structure sufficient to support the body lumen.

742. A stent prosthesis as in clause 675, wherein the stent has initialstrength after expansion and wherein the strength diminishes afterformation of said discontinuities, and wherein the stent retains asufficient stent structure to support the body lumen.

743. A stent prosthesis as in clause 675, wherein the stent has initialstrength after expansion and wherein the strength diminishes afterformation of said discontinuities, and wherein the stent retains asufficient stent structure to support a vulnerable body lumen.

744. A stent prosthesis as in clause 675, wherein at least some of theseparation regions allow the structural elements adjacent to saidseparation regions to move in one or more direction

745. A stent prosthesis as in clause 675, wherein at least some of theseparation regions allow the structural elements adjacent to saidseparation regions to move in one or more directions comprising radial,or circumferential.

746. A stent prosthesis as in clause 675, wherein at least someseparation regions are held together in the stent crimped configurationby a key and lock junction to facilitate expansion of the stent

747. A stent prosthesis as in clause 675, wherein at least someseparation regions are held together by adhesive, polymer, orcombination thereof.

748. A stent prosthesis as in clause 675, wherein at least someseparation regions have a gap, said gap magnitude ranges from 0.05 mm to0.2 mm, and wherein the gap allows the structural elements adjacent tosaid separation regions to move in a circumferential direction afterformation of discontinuities, and wherein the movement ranges from 0.05mm to 2 mm.

749. A stent prosthesis as in clause 675, wherein at least someseparation regions are located on non-deformable or substantiallynon-deformable regions of the circumferential rings

750. A stent prosthesis as in clause 675, wherein substantially allseparation regions are located on non-deformable or substantiallynon-deformable regions of the circumferential rings

751. A stent prosthesis as in clause 675, wherein substantially allseparation regions are located on strut regions of the circumferentialrings

752. A stent prosthesis as in clause 675, wherein at least someseparation regions are located on crown regions of the circumferentialrings, and wherein the separation regions allow the crown region todeform open upon expansion of the stent without breaking of the crownregion.

753. A stent prosthesis as in clause 675, wherein the stent longitudinalstructure is substantially maintained after formation of saiddiscontinuities.

754. A stent prosthesis as in clause 675, wherein the longitudinalstructure of the stent remains substantially connected after formationof said discontinuities

755. A stent prosthesis as in clause 675, wherein the stent in thelongitudinal direction forms one to four semi-circular strips connectedin the longitudinal direction by one or more links after formation ofsaid discontinuities, and wherein the stent substantially maintains apatterned structure.

756. A stent prosthesis as in clause 675, wherein at least some of thecrowns and struts regions on every ring do not have separation regions.

757. A stent prosthesis as in clause 675, wherein substantially allcrown regions on at least some rings do not have separation regions.

758. A stent prosthesis as in clause 675, wherein substantially alldeformable regions on at least some rings do not have separationregions.

759. A stent prosthesis as in clause 675, wherein the separation regionsare smaller than the strut and/or crown regions.

760. A stent prosthesis as in clause 675, wherein the separation regionsform a gap in the crimped stent configuration.

761. A stent prosthesis as in clause 675, wherein the number ofseparation regions on at least some rings are equal to or less than ½the number of crowns on said rings, or the number of separation regionson at least said rings are equal to or less than ¼ the number of strutson said rings, wherein the stent prosthesis after formation ofdiscontinuities substantially maintains a patterned structure sufficientto support a body lumen.

762. A stent prosthesis as in clause 675, wherein the number ofseparation regions on each ring are equal to or less than ½ the numberof crowns on said ring, and/or the number of separation regions on eachring are equal to or less than ¼ the number of struts on said ring,wherein the stent prosthesis after formation of discontinuitiessubstantially maintains a patterned structure sufficient to support abody lumen.

763. A stent prosthesis as in clause 675, wherein the number ofseparation regions on each ring are equal to or less than 4/6 the numberof crowns on said ring, and/or the number of separation regions on eachring are equal to or less than ½ the number of struts on said ring,wherein the stent prosthesis after formation of discontinuitiessubstantially maintains a patterned structure sufficient to support abody lumen.

764. A stent prosthesis as in clause 675, wherein the number ofseparation regions on each ring are equal to or less than 4/6 the numberof crowns on said ring, and/or the number of separation regions on eachring are equal to or less than ½ the number of struts on said ring,wherein the stent prosthesis after formation of discontinuitiessubstantially maintains a patterned structure sufficient to support abody lumen, wherein the radial strain of said stent prosthesis is lessthan the radial strain of the unstented lumen adjacent to the stentprosthesis.

765. A stent prosthesis as in clause 675, wherein the stent is formedfrom a metal or metal alloy and patterned into a stent by laser.

766. A stent prosthesis as in clause 675, wherein at least some ringscontain at least some separation regions, and wherein the separationregions comprise a gap region along the circumferential path of said atleast some rings, and wherein the gap comprises a biodegradable materialconnecting the two ends of the separation regions and hold them togetherin the crimped configuration, and wherein the polymeric materialdegrades after expansion of the stent forming discontinuities in saidcircumferential rings.

767. A stent prosthesis as in clause 675, wherein the stent comprisesopen cell type design, closed cell type design, helical type design,coil type design, or combination thereof.

768. A stent prosthesis as in clause 675, wherein the distance betweenat least some adjacent rings ranges from 0.05 mm to 3 mm, preferablyranges from 0.1 mm to 2 mm, more preferably ranges from 0.2 mm to 1 mm.

769. A stent prosthesis as in clause 675, wherein the distance betweenany adjacent rings ranges from 0.05 mm to 3 mm, preferably ranges from0.1 mm to 2 mm, more preferably ranges from 0.2 mm to 1 mm.

770. A stent prosthesis as in clause 675, wherein the shortest distancebetween any adjacent rings ranges from 0.01 mm to 1 mm, preferablyranges from 0.05 mm to 1 mm, more preferably ranges from 0.1 mm to 1 mm.

771. A stent prosthesis as in clause 675, wherein the longest distancebetween any adjacent rings ranges from 0.1 mm to 3 mm, preferably rangesfrom 0.15 mm to 2.5 mm, more preferably ranges from 0.15 mm to 2.3 mm.

772. A stent prosthesis as in clause 675, wherein the at least somerings in the absence of separation regions form circumferentiallycontinuous rings in the expanded stent configuration.

773. A stent prosthesis as in clause 675, wherein the at least someseparation regions are held together in the crimped configuration andremain held together upon expansion of the stent prosthesis from saidcrimped configuration.

774. A stent prosthesis as in clause 675, wherein the expansion of thestent prosthesis from said crimped configuration to said expanded largerconfiguration does not form discontinuities in said separation regions.

775. A stent prosthesis as in clause 675, wherein the discontinuitiesform passively under physiologic conditions

776. A stent prosthesis as in clause 675, wherein the discontinuitiesform after expansion of the stent to the expanded configuration andunaided by any device to form said discontinuities

777. A stent prosthesis as in clause 675, wherein the stent structuralelements in the crimped configuration do not overlap.

778. A stent prosthesis as in clause 675, wherein substantially all thestent structural elements, with the exception of at least someseparation regions, in the crimped configuration do not overlap.

779. A stent prosthesis as in clause 675, wherein the stent structuralelements in the expanded configuration do not overlap

780. A stent prosthesis as in clause 675, wherein substantially all thestent structural elements in the expanded configuration with theexception of at least some separation regions do not overlap

781. A stent prosthesis as in clause 675, wherein the stent structuralelements do not roll in the crimped configuration.

782. A stent prosthesis as in clause 675, wherein the stent structuralelements are crimped as one layer over the delivery system.

783. A stent prosthesis as in clause 675, wherein the stent structuralelements are crimped as one layer within the delivery system.

784. A stent as in clause 675, wherein the stent is a substantiallycylindrical structure in the expanded configuration and wherein thestent have continuous circumferential elements with the exception of theat least some separation regions, and wherein the stent expands from acrimped configuration to an expanded configuration radially.

785. A stent as in clause 675, wherein the stent is a substantiallycylindrical structure in the expanded configuration and wherein thestent have continuous circumferential elements with the exception of theseparation regions, and wherein the expands from a crimped configurationto an expanded configuration not circumferentially

786. A stent as in clause 675, wherein the stent is a substantiallycylindrical structure in the expanded configuration and wherein thestent expands from a crimped configuration to an expanded configurationnot by a sliding means

787. A stent prosthesis as in clause 675, wherein the separation regionsdo not form discontinuities upon expansion of the stent prosthesis, andwherein the discontinuities form after expansion of the stent.

788. A stent prosthesis as in clause 675, wherein the separation regionsdo not form a substantially straight line of discontinuities along thelength of the stent

789. A stent prosthesis as in clause 675, wherein the separation regionsdo not form a straight line of discontinuities along substantially thelength of the stent

790. A stent prosthesis as in clause 675, wherein the stent prosthesisafter formation of discontinuities have improved longitudinalflexibility in the expanded configuration while substantially all theaxial links connecting at least some adjacent rings are substantiallyintact.

791. A stent prosthesis comprising: a non-degradable metal or metalalloy material, said material patterned into a substantially cylindricalstructure capable of being expandable from a crimped configuration to anexpanded larger configuration, and have sufficient strength in theexpanded configuration to support a body lumen, said structure comprisesstructural elements comprises a plurality of circumferential rings,wherein at least some circumferential rings are connected to adjacentrings via one or more axial links, and/or via connecting at least somestructural element regions on said at least some rings to structuralelement regions on said adjacent rings; wherein each ring comprisesstruts joined by crowns, and wherein the at least some circumferentialrings have one or more separation regions along the circumferential pathof said rings, and wherein said separation regions form discontinuitiesafter expansion; wherein said stent and/or said at least some ringsafter formation of said discontinuities exhibit one or more of thefollowing: a radial strain ranging between 1% and 5%, a radialdisplacement ranging from 0.05 mm to 1.5 mm, further expand to a largerexpanded configuration after inward recoil from said expandedconfiguration, vaso-dilatation and/or vaso-constriction in the magnituderanging from 0.05 mm to 0.3 mm, reduction in strength, uncagingcircumferentially, or reduction in hoop stresses, under physiologicconditions; and wherein the at least some rings having one or moreseparation regions remain substantially connected to adjacent ringsafter expansion.

792. A stent prosthesis comprising: a degradable metal or metal alloymaterial, said material patterned into a cylindrical structure capableof being expandable from a crimped configuration to an expanded largerconfiguration, and have sufficient strength in the expandedconfiguration to support a body lumen, said structure comprisesstructural elements comprises a plurality of circumferential rings,wherein at least some circumferential rings are connected to adjacentrings via one or more axial links, and/or via connecting at least somestructural element regions on said at least some rings to structuralelement regions on said adjacent rings; wherein each ring comprisesstruts joined by crowns, and wherein the at least some circumferentialrings have one or more separation regions along the. circumferentialpath of said rings, and wherein said separation regions formdiscontinuities after expansion; and wherein said stent and/or said atleast some rings after formation of said discontinuities exhibit one ormore of the following: a radial strain ranging between 1% and 5%, aradial displacement ranging from 0.05 mm to 1.5 mm, further expand to alarger expanded configuration after inward recoil from said expandedconfiguration, vaso-dilatation and/or vaso-constriction in the magnituderanging from 0.05 mm to 0.3 mm, reduction in strength, uncagingcircumferentially, or reduction in hoop stresses, under physiologicconditions, and wherein the at least some rings having one or moreseparation regions remain substantially connected to adjacent ringsafter expansion, and wherein the degradable material comprises on ormore of magnesium, tungsten, or other degradable metal or metal alloysas described in the specifications.

793. A stent prosthesis comprising: a non-degradable metal or metalalloy formed from a tube or one or more wires and patterned into asubstantially cylindrical stent capable of expansion from a crimpedconfiguration to an expanded larger configuration and have sufficientstrength in the expanded configuration to support a body lumen, saidstent comprises structural elements comprising a plurality ofcircumferential rings wherein at least some rings have from 1 to 5separation regions along the circumferential path of said rings, andwherein the separation regions form discontinuities after expansionreducing said stent strength but substantially maintaining open saidbody lumen, said stent has an initial radial strain and wherein saidradial strain increases after formation of discontinuities.

794. A stent prosthesis comprising: formed from a non-degradable metalor metal alloy and patterned into a substantially cylindrical structurecapable of expansion from a crimped configuration to an expanded largerconfiguration and have sufficient strength in the expanded configurationto support a body lumen, said stent structure comprises structuralelements comprising a plurality of circumferential rings wherein atleast some rings have from 1 to 5 separation regions along thecircumferential path of said rings, and wherein the separation regionsform discontinuities after expansion of the stent reducing the said atleast some rings strength while increasing the said at least some ringsradial strain, under physiologic conditions.

795. A stent prosthesis comprising: formed from a non-degradable metalor metal alloy and patterned into a substantially cylindrical structurecapable of expansion from a crimped configuration to an expanded largerconfiguration and have sufficient strength in the expanded configurationto support a body lumen, said stent structure comprises structuralelements comprising a plurality of circumferential rings wherein atleast some rings have from 1 to 5 separation regions along thecircumferential path of said rings, and wherein the separation regionsform discontinuities after expansion of the stent increasing thedisplacement in at least one axis of the said at least some rings, underphysiologic conditions.

796. A stent prosthesis comprising: formed from a non-degradable metalor metal alloy and patterned into a substantially cylindrical structurecapable of expansion from a crimped configuration to an expanded largerconfiguration and have sufficient strength in the expanded configurationto support a body lumen, said stent structure comprises structuralelements comprising a plurality of circumferential rings wherein atleast some rings have from 1 to 5 separation regions along thecircumferential path of said rings, and wherein the separation regionsform discontinuities after expansion of the stent increasing thedisplacement in at least one direction of the said at least some rings,under physiologic conditions.

797. A stent prosthesis comprising: formed from a non-degradable metalor metal alloy and patterned into a substantially cylindrical structurecapable of expansion from a crimped configuration to an expanded largerconfiguration and have sufficient strength in the expanded configurationto support a body lumen, said stent structure comprises structuralelements comprising a plurality of circumferential rings wherein atleast some rings have from 1 to 5 separation regions along thecircumferential path of said rings, and wherein the separation regionsform discontinuities after expansion of the stent increasing thedisplacement in at least one or more of axial, circumferential, radial,or longitudinal direction, of the said at least some rings, underphysiologic conditions.

Variable Compliance Clauses

798. A variably compliant stent prosthesis comprising: a non-degradablemetal or metal alloy scaffold expandable from a crimped configuration toan expanded larger configuration; wherein after expansion the scaffoldhas sufficient strength to support a vascular lumen; and whereinimmediately but no later than 1 hour after expansion the scaffold has acomposite compliance when measured in a mock vessel no greater than 1%;and wherein after expansion and exposure to vascular conditions, thecomposite compliance when measured in a mock vessel increases to atleast 1.5%.

799. A variably compliant stent prosthesis comprising: a non-degradablemetal or metal alloy scaffold expandable from a crimped configuration toan expanded larger configuration; wherein after expansion the scaffoldhas sufficient strength to support a vascular lumen; and whereinimmediately but no later than 1 hour after expansion the scaffold has aninitial composite compliance when measured in a mock vessel; and whereinafter expansion and exposure to exposure to vascular conditions, thecomposite compliance when measured in a mock vessel increases by afactor of at least two.

800. A variably compliant stent prosthesis as in clause 798 or 799,wherein the non-degradable metal or metal alloy scaffold comprisesseparation regions which separate after exposure to vascular conditionsfor a threshold time period.

801. A variably compliant stent prosthesis as in clause 800, wherein atleast some of the separation regions are initially prevented fromseparating by a bioabsorbable material which degrades over time whenexposed to the vascular conditions.

802. A variably compliant stent prosthesis as in clause 801 wherein thebioabsorbable material is in the form of a coating, sleeve, or adhesive.

803. A variably compliant stent prosthesis as in clause 801 wherein thebioabsorbable material degrades over a time period in a range from 30days to 12 months when exposed to the vascular conditions.

804. A variably compliant stent prosthesis as in clause 798 or 799,wherein the non-degradable metal or metal alloy scaffold comprisesregions reinforced with a reinforcement material wherein thereinforcement material degrades after exposure to vascular conditionsfor a threshold time period.

805. A variably compliant stent prosthesis as in clause 804, wherein thereinforcement material comprises a bioabsorbable material which degradesover time when exposed to the vascular conditions.

806. A variably compliant stent prosthesis as in clause 804, wherein thereinforcement material fills voids in a crown and/or a strut of thenon-degradable metal or metal alloy scaffold.

807. A variably compliant stent prosthesis as in clause 805, wherein thereinforcement material covers or coats at least a region of a surface ofthe non-degradable metal or metal alloy scaffold.

808. A variably compliant stent prosthesis as in clause 798 or 799,wherein immediately but no later than 1 hour after expansion thescaffold has a strength (initial strength) in the range from 0.035Newton per millimeter of stent length to 0.1 Newton per millimeter ofstent length.

809. A variably compliant stent prosthesis as in clause 808, wherein theradial strength of the stent scaffold decreases after expansion andexposure to vascular conditions.

810. A variably compliant stent prosthesis as in clause 808, wherein theradial strength of the stent scaffold increases from the initialstrength before decreasing after expansion and exposure to vascularconditions.

811. A variably compliant stent prosthesis as in clause 809, wherein theradial strength of the stent scaffold decreases by from 20% to 100%after expansion and exposure to vascular conditions, optionally by from20% to 80%.

812. A variably compliant stent prosthesis as in clause 798 or 799,wherein the non-degradable metal or metal alloy scaffold has a nominalexpanded diameter, wherein the strength and composite compliance aremeasured after the stent has been expanded to a diameter of from 80% to120% of the nominal expanded diameter, optionally at 100% of the nominalexpanded diameter.

In a preferred example, the scaffold is a stent, wherein the stentcomprises one or more circumferential rings joined axially, and whereinthe one or more rings comprise struts and crowns. Stents include stentgrafts, endoprostheses, ecto-prostheses (prostheses surrounding theexterior of a blood vessel or other body lumen), and other luminalprostheses intended to be implanted in a blood vessel, annulus, or otherbody lumen. The scaffold usually is a patterned cylindrical,substantially cylindrical, tubular, or substantially tubularcircumferential structure and is constructed so that it can beintroduced to the blood vessel, annulus, or other body lumen in a“crimped” configuration, i.e. in a low or reduced profile that allowsthe scaffold to be advanced to a target location within the body lumenwhere it is expanded to an “expanded configuration” where an outersurface of the scaffold contacts and/or supports the inner wall of thebody lumen to maintain patency. In some cases, such as with “bare”stents, the scaffold may comprise a metal, metal alloy, plastic, orother conventional stent material which typically has been patternedfrom a tube, from a sheet, or from one or more wires, and is configuredto be inserted into the lumen of an anatomic vessel or duct or otherlumen in the crimped configuration. After insertion, the scaffold may beradially enlarged to the expanded configuration to keep a luminalpassageway open or to open a closed, typically diseased passageway. Inother cases, the scaffold may comprise one or more additional material(such as polymeric material) and/or one or more drugs, e.g. the scaffoldmay additionally have one or more coatings on at least one surface ofthe stent, the scaffold may be coated on at least one surface with adrug or other active substance to be a drug-coated stent, or the like.In still other instances, scaffold may form a portion of a prostheticheart valve, vein valve, or other implantable valve.

In another preferred example, the separation region is a location in thescaffold which, prior to exposure to physiologic conditions andformation of discontinuities, will have sufficient structural integrityand strength to remain intact while the scaffold is expanded in a bloodvessel or other similar or equivalent physiologic environment orconditions. Such expansion will typically be effected by inflation of adeployment balloon within a central lumen of the scaffold which canapply significant hoop stresses on the scaffold. The separation regionswill be formed to withstand such stresses, e.g. by joining, covering,embedded, gluing, or otherwise immobilizing the separation region with amaterial which remains intact during scaffold expansion but which willsubsequently degrade or otherwise detach from the scaffold in thephysiologic environment to allow formation of a discontinuity.Alternatively, the scaffolds can be self-expanding, but the separationregions will still be formed to withstand stresses resulting from theself-expansion.

In another preferred example, a discontinuity comprises an opening, gap,joint, elastic junction, or the like, which forms in the scaffold at thelocations of the separation regions after expansion of the scaffold andexposure of the scaffold to a blood vessel or other similar orequivalent physiologic environment or conditions. The discontinuitieswill increase the radial compliance of the scaffold or at least portionsthereof. The discontinuities will be at locations in the expandedscaffold which decrease the hoop strength of the expanded scaffoldsafter the discontinuities form. For example, discontinuities may be incircumferential rings of a scaffold and will decrease the resistance tocircumferential expansion of the ring, thus increasing radial complianceof the ring and of the scaffold as discussed in detail elsewhere in thisapplication. In contrast, a discontinuity or break in an axial link orother axial connection which holds adjacent circumferential ringstogether typically will not decrease the hoop or radial strength of theexpanded rings or scaffolds after the discontinuities form and typicallywill not increase radial compliance of the rings or scaffold as is anobject of the present invention.

In another preferred example, the phrase “after all discontinuities areformed,” refers to the scaffold when all separation regions in ascaffold have separated and all discontinuities have formed. Whilediscontinuities may not always form in all separation regions in ascaffold after implantation in a blood vessel or other physiologyenvironment, even though the separation regions maybe configured to formdiscontinuities at each separation region within the scaffold, all ofthe separation regions can be caused to form during in vitro tests runto determine if a scaffold meets the physical characteristics claimedherein. Thus, for the purposes of determining whether a scaffold meetsthe requirements of a claim which requires a determination that “alldiscontinuities are formed,” the scaffold may be examined and testedafter exposure to in vitro conditions selected to form alldiscontinuities by mimic in vivo physiologic condition, such assalinity, temperature, pressure, addition of agents or material to causeformation of discontinuities, and the like, which would be expected toresult in formation of discontinuities at each separation region withinthe scaffold. Examples of such in vitro physiologic conditions areprovided in the Examples Section hereinbelow.

In another preferred example, the word “pattern” refers to the geometricarrangement of the structural elements of a scaffold. The most commonpattern comprises a plurality of “circumferential rings” which areaxially joined, either by axial links or by direct attachment of axiallyadjacent regions on the circumferential rings. The scaffolds of thepresent invention may also have helical patterns, diamond and otherclosed or open cell patterns, and other patterns known in the vascularand other stent fabrication arts. The circumferential rings will usuallybe formed as serpentine or zig-zag structures comprising struts joinedby crowns, where the struts will usually be straight (but can be notstraight) and the crowns will act as joints or hinges to allow thestruts to open and the circumferential ring to expand bothcircumferentially and radially. That is, the distance around thecircumference or perimeter of the circumferential ring will increase aswill the radial distance of the ring perimeter from the axial center ofthe scaffold.

In another preferred example, the individual circumferential rings of ascaffold will usually be “intact” and will usually be “axially joined”when the scaffold is in its crimped configuration prior to expansion orformation of discontinuities. By “intact,” it is meant that thecircumferential ring will have a continuous serpentine, zig-zag,sinusoidal, or other circumferential structure free fromdiscontinuities. By “axially joined,” it is meant that axially adjacentcircumferential rings will be joined by axial links, or by directcrown-to-crown attachment by fusing or soldering, for example. Afterexpansion of the scaffold and exposure to a physiologic environment,discontinuities will form in at least some of the rings, typically beinggaps, breaks, or bisections in a strut or crown region or otherstructural component which forms the peripheral path or perimeter of thering so that the ring structure is no longer continuous. Even though theindividual circumferential rings may thus divide into two or moreseparated portions (partial circumferential rings) after formation ofdiscontinuities, they may also be refereed to as “circumferential rings”as that phrase is used herein and in the claims and, in particular,adjacent circumferential rings will be considered to remain “axiallyjoined” (intact) so long as at least one portion of one ring remainsconnected to at least one portion of an adjacent ring even if the joinedportions of a circumferential ring are separated by discontinuities fromother portions of the same ring.

In another preferred example, “radial compliance” is the compositecompliance of the scaffold, stent, prosthesis or other structuremeasured as a composite compliance in vitro in a mock vessel (or tube)in accordance with ASTM F2477-07R13 which measures compliance at apressure change of 100 mmHg, or radial strain (compliance measure atother pressure changes such as at about 176 mmHg), but the test can alsoprovide the method for testing compliance at a given change in pressureother than 100 mmHg.

In another preferred example, “segment” and the phrase “segment of ascaffold” refer to a structural component of the scaffold which willremain joined or intact after all discontinuities have formed in thescaffold. For example, a circumferential ring is a segment as well as aclosed cell structure. In many instances, two or more segments of thescaffold will remain joined after all discontinuities have formed in thescaffold. Thus, while segments will always remain joined or intact(where intact connotes that the structure is joined without anydiscontinuities, segments which are initially joined may or may notremain joined after all discontinuities have formed in the scaffold.

In another preferred example, “circumferential ring” refers both torings with a continuous perimeter or periphery which extends over a full360° as well as to discontinuous rings which have an offset in theirperimeter or periphery. Such discontinuous circumferential rings willoften be successively joined end-to-end so that they together form ahelical pattern along all or a portion of the length of the scaffold.The individual circumferential rings will thus form successive turns ofthe helical scaffold. In one example, the circumferential ring patternmay be perpendicular to the longitudinal axis of the stent in thecrimped and/or expanded configuration. In another example, thecircumferential rings pattern may be at an angle between perpendicularto the stent longitudinal axis in the crimped configuration and/orexpanded configuration and the stent longitudinal axis in the crimpedand/or expanded configuration.

In another preferred example, “physiologic environment” refers both tonatural or endogenous environments, typically a patient vasculature orother luminal environment, as well as to artificial or in vitroenvironments intended to mimic an endogenous vascular or other naturalluminal environment. In particular, the artificial or in vitroenvironments will have at least some of the same temperature such as 37°C., aqueous solution (water bath), pressure change of about 100 mm Hg orof about 200 mmHg, mock tube having an inner diameter of 3.0 mm and acompliance of about 5%, agents to accelerate formation ofdiscontinuities, and other characteristics of the endogenous environmentthat can be used to test the scaffolds to see if the separation regionswill form discontinuities, stretch, or have enhanced compliance, inaccordance with the principles of the present invention. In particular,to determine if a scaffold has separations regions, the scaffold can beexamined for such separation regions, and/or be exposed to thephysiologic conditions in vitro as described herein and observed to seeif discontinuities form, or to test the scaffold for enhanced compositecompliance, or to test the scaffold for initial compliance and increasedcomposite compliance, or to test for the scaffold radial initial radialstrength, or to test for radial strength after formation ofdiscontinuities, the scaffold can be expanded in a tube “mock vessel”having ID of 3.0 mm, tube compliance of about 5%, in water bath at 37 C,and a pressure change of 100 mmHg, expand the inner scaffold diameter toabout 110% of the tube inner diameter to ensure a good fit into thetube, measure initial composite compliance, dissolve the materialholding the separation regions together forming discontinuities, andremeasure the composite compliance, the compliance of the stentedsegment at a mid segment of the stented segment, the compliance inaccordance with the present invention increases from initial compositecompliance after formation of discontinuities, typically increases by200%-500% of the initial composite compliance, or usually increases by200%-300%, or increases by at least 200% of the initial compositecompliance, or increases by at least 300%.

In one preferred example, the stent after formation of discontinuitiesseparates into 2, or 3, or 4 separate stent sections along the length ofthe stent, each section comprising a plurality of partialcircumferential rings, where each partial ring remain axially connected(intact) to an adjacent partial ring, where the 2, 3, or 4 separatesections are formed after all the separation regions in eachcircumferential ring form discontinuities.

In a preferred example, the phrases “stent compliance,” “stented segmentcompliance,” and “stent vessel system compliance,” all refer to thecomposite compliance of the stented/scaffolded segment as described inthe composite compliance test method.

In a preferred example, the radial strength is measured using the flatplate (10% compression) test as described in the radial test methoddescribed in the application.

In a preferred example, at least some rings of the scaffold or stent ofthe present invention, are preferably which are formed fromnon-degradable metal or metal alloys, after expansion from a crimpedconfiguration to an expanded configuration in a body lumen (or mockvessel), exhibit one or more of the following after formation ofdiscontinuities compared to before formation of discontinuities: (1)uncage at least some, preferably all circumferential rings (the stent),or the stented segment, (2) display a change in configuration ordiameter of at least some rings, preferably all rings of the stentedsegment, (3) display further expansion of at least some rings of thestented segment, (4) at least some rings of the stented segment, usuallyall, are able to expand and/or contract in a range from 0.1 mm to 0.5mm, under physiologic conditions including contractility of the heartand/or change in pressure. Physiologic conditions may also includesimulated physiologic conditions. Examples of the above are shown inexample 22, showing OCT images of separation regions formingdiscontinuities in at least some rings uncaging said ringscircumferentially, showing the opposite ends of at least some struts(containing the separation region) separate after formation ofdiscontinuities and move radially and/or circumferentially (out of planecompared to each other), and/or showing a change in configuration ordiameter of the at least some rings, or the stent further expand to alarger diameter or configuration after expansion and initial inwardrecoil from expansion of any, as shown in FIG. 100B-D or 101A-B. Theabove may also be shown in other tests bench, in-vitro, or in-vivo.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a prior art endoluminal prostheses comprising acircumferential scaffold having a plurality of expansible rings.

FIGS. 2A and 2B are “rolled-out” illustrations of the endoluminalprosthesis of FIG. 1.

FIGS. 3A and 3B are “rolled-out” illustrations of a prior artendoluminal prosthesis similar to that of FIGS. 1, 2A and 2B, exceptthat the rings are serpentine rings rather than zig-zag rings.

FIGS. 4A and 4B illustrate the serpentine circumferential scaffold ofFIGS. 3A and 3B modified or configured with the reinforcement elementsof the present invention in a first reinforcement pattern example.

FIGS. 5A and 5B illustrate the serpentine circumferential scaffold ofFIGS. 3A and 3B with reinforcement elements and a second reinforcementpattern example.

FIGS. 6A and 6B illustrate the circumferential scaffold of FIGS. 3A and3B with reinforcement elements in a third reinforcement pattern example.

FIGS. 7A and 7B illustrate the serpentine circumferential scaffold ofFIGS. 3A and 3B with reinforcement elements in a fourth reinforcementpattern example.

FIGS. 8A and 8B illustrate the serpentine circumferential scaffold ofFIGS. 3A and 3B with reinforcement elements in a fifth reinforcementpattern example.

FIGS. 9A-9C illustrate various examples of coupled (attaching and/orembedding) reinforcement elements into a serpentine ring for example orother component or structural elements of a circumferential scaffold inaccordance with the principles of the present invention.

FIG. 9D illustrates coupling (attachment) of an external reinforcementelement to a serpentine ring segment.

FIG. 10 is an enlarged view of a single zig-zag showing partial ring ofthe circumferential scaffold of the endoluminal prosthesis of FIGS. 1,2A, and 2B.

FIGS. 11A and 11B illustrate modification of a hinge of for example theserpentine ring of FIG. 10 which is suitable to promote formation of abreak, discontinuity, and/or detachment in accordance with theprinciples of the present invention.

FIGS. 12A and 12B illustrate the modification of a strut of for examplethe zig-zag ring of FIG. 10 in order to promote formation of a break,discontinuity, and/or detachment.

FIGS. 13A and 13B illustrate a modification to hinge regions in thevicinity of an axial link of the zig-zag ring of FIG. 10 in order topromote formation of a discontinuity and detachment in the hinge regionin accordance with the principles of the present invention.

FIGS. 14A and 14B illustrate an alternative hinge or joint structurewhich may be used for example in a serpentine ring structure in order topromote formation of a break, separation, discontinuity, and/ordetachment in accordance with the principles of the present invention.

FIGS. 15A and 15B illustrate modification example of the grain structureof a hinge region of the zig-zag ring of FIG. 10 to promote formation ofa break, discontinuity, and/or detachment in accordance with theprinciples of the present invention.

FIGS. 16A-16D illustrate different examples of separation regionssuitable for strut separation in the circumferential rings of thepresent invention.

FIGS. 16E-1 through FIG. 16E-3 illustrate an alternative separationregion pattern examples which may be joined by a biodegradable sleeve orby a biodegradable adhesive or a biodegradable polymer and whichseparates by strut displacement or movement in a preferably radialdirection only but can also move in circumferential, and/or in an axialdirection in some cases.

FIGS. 16F-1 through FIG. 16F-5 illustrate another alternative separationregion pattern which may be joined by a biodegradable sleeve or by abiodegradable adhesive or by a biodegradable polymer and which separatesby strut displacement or movement in a radial direction, circumferentialdirection, and/or an axial direction.

FIGS. 16G-1 through FIG. 16G-3 illustrate still another alternativeseparation region pattern example which has an extended axial interfacebetween the abutting strut segments which is particularly suitable forjoining with a biodegradable adhesive but may be also joined by abiodegradable sleeve or biodegradable polymer and which separates bystrut displacement or movement in a radial direction, circumferentialdirection, and/or an axial direction.

FIGS. 16G-4 through FIG. 16G-10 illustrate exemplary separation patternsfor tubular prostheses as an example constructed in accordance with theprinciples of the present invention.

FIG. 16G-11 illustrates a stent having separation regions in combinationwith resilient reinforcement elements configured to control and/orassist opening of the stent.

FIGS. 16H-1 through FIG. 16H-5 illustrate still further examples ofseparation region patterns which rely on a core member received inhollow regions or receptacles in adjacent strut segments whichpreferentially separate by strut displacement in an axial directionand/or radial (or circumferential) direction.

FIGS. 16I-1 through FIG. 16I-4 illustrate additional examples ofseparation region having differently shaped interface surfaces onadjacent strut segments.

FIG. 16I-5 and FIG. 16I-6 illustrate still further examples ofseparation region having surface features for enhancing degradableimmobilization with adhesives, cements, polymers, sleeves, or otherimmobilizing components.

FIGS. 16I-7 through FIG. 16I-16C illustrate separation regionscharacterized by gaps in struts and/or crowns, and/or optionally havingdegradable bridges in the gaps, and/or having separation regions withbridging elements.

FIG. 17 illustrates a further example of a separation region which maybe located between a pair of adjacent circumferential rings in thecircumferential scaffolds of the present invention.

FIG. 18 illustrates the optional use of an alignment pin in a separationregion in accordance with the principles of the present invention.

FIG. 19 illustrates a magnetically joined separation region for use inthe circumferential rings of the present invention.

FIG. 20 illustrates an alternative example of connection for aseparation region in a strut in accordance with the principles of thepresent invention.

FIG. 21 illustrates an example of an alignment pin in a tubular strutstructure in accordance with the principles of the present invention.

FIG. 22 illustrates the use of a sacrificial constraint such as a sleevefor constraining a hinge region in the circumferential ring inaccordance with the principles of the present invention.

FIG. 22A and FIG. 22B illustrate a further type of separation regionwhere a pair of adjacent struts in a circumferential ring are separatedand collapsed in parallel and optionally held together with a degradablesleeve.

FIGS. 23A and 23B illustrate an example of a joint or separation regionplaced in a hinge of a circumferential ring in accordance with theprinciples of the present invention.

FIGS. 23C and 23D illustrate example of a joint or separation regionplaced in a hinge with supporting features of a circumferential ring inaccordance with the principles of the present invention.

FIGS. 23E-1 through 23E-3 illustrate the use of separation regions toform a stent which preferentially opens an aperture at a bifurcationregion.

FIGS. 24A, 24B, 25A-25C, 26A-26C, 27A, 27B, 28-31, 32, 32A, 32B, 33,33A, 33B, 34 and 35 illustrate stents fabricated and tested inaccordance with the principles of the present invention. FIG. 35 is anexample of a test apparatus for fatigue testing, radial strain(compliance) testing, displacement magnitude testing, contraction and/orexpansion of the stent in the deployed configuration testing, and other,of the stent segment.

FIG. 35A is a graph showing the % change in vessel diameter of the midsegment of the stent implanted in the coronary artery of a porcine modelas described in Example 20.

FIG. 36 illustrates a helical stent structure found in the prior art andhaving a helically wound serpentine backbone (rings).

FIG. 37 illustrates a first example or embodiment of a stent with ahelical backbone (rings) including separation region between individualturns of the stent rings constructed in accordance with the principlesof the present invention, additionally including a separation regions inthe crown and strut of a ring.

FIG. 38 illustrates a second example or embodiment of a stent with ahelical backbone including separation regions (not illustrated) withinindividual turns of the stent rings constructed in accordance with theprinciples of the present invention, and a separation region betweenturns.

FIG. 39 illustrates a third example or embodiment of a stent with ahelical backbone including separation region between individual turns ofthe stent constructed in accordance with the principles of the presentinvention.

FIG. 40 illustrates a fourth example or embodiment of a stent with ahelical backbone including separation regions between individual turnsof the stent rings constructed in accordance with the principles of thepresent invention.

FIG. 41 illustrates a fifth example or embodiment of a stent with ahelical backbone including separation regions between individual turnsof the stent rings constructed in accordance with the principles of thepresent invention.

FIG. 42 illustrates a sixth example or embodiment of a stent with ahelical backbone including separation regions between individual turnsof the stent rings constructed in accordance with the principles of thepresent invention.

FIG. 43 illustrates a first example or embodiment of a closed-cell stentscaffold joined by circumferential separation regions where theseparation regions are located in circumferential connectors of therings, and sturts, in accordance with the principles of the presentinvention.

FIG. 44 illustrates a second example or embodiment of a closed-cellstent scaffold joined by circumferential separation regions where theseparation regions are located in circumferential connectors of ringsand crowns, in accordance with the principles of the present invention.

FIG. 45 illustrates a third example or embodiment of a closed-cell stentscaffold joined by circumferential separation regions where theseparation regions are located in circumferential connectors of therings and struts, in accordance with the principles of the presentinvention.

FIG. 46 illustrates a fourth example or embodiment of a closed-cellstent scaffold joined by separation regions in accordance with theprinciples of the present invention.

FIGS. 46A and 46B illustrate an example or embodiment of a stentscaffold having zig-zag circumferential rings which are joined bydirectly attaching crowns, preferably without an intermediate linkelement.

FIG. 47 illustrates a scaffold having a straight backbone with aplurality of circumferential rings having staggered gaps distributedover its length.

FIG. 48 illustrates a scaf 1239, and fold having a non-aligned backbonesegments joining a plurality of circumferential rings having staggeredgaps.

FIG. 49 illustrates an exemplary circumferential ring of a stentprosthesis modified to include a pair of circumferential displacementregions in individual struts thereof.

FIGS. 50-52 illustrate the circumferential displacement regions of FIG.49 in greater detail.

FIGS. 53 and 54 illustrate a first alternative construction of acircumferential displacement region of a type which could be employed inthe circumferential ring of FIG. 49.

FIG. 55 illustrates a second alternative construction of a displacementregion such as a circumferential displacement region of a type whichcould be employed in the circumferential ring of FIG. 49.

FIGS. 56, 57, 58A, and 58B illustrate a fourth alternative constructionof a displacement region such as a circumferential displacement regionof a type which could be utilized in the circumferential ring of FIG.49.

FIGS. 59 and 60 illustrate a fifth alternative construction of adisplacement region such as a circumferential displacement region of atype which could be employed in the circumferential ring of FIG. 49.

FIGS. 61, 62A and 62B illustrate an alternative stent prosthesisstructure having displacement region such as circumferentialdisplacement regions present on axial links adjoining adjacentcircumferential stent rings.

FIG. 63 illustrates a stent structure fabricated as three separatepanels intended for subsequent assembly into a complete stent.

FIGS. 64A-64D illustrate exemplary steps for fabricating the panels ofFIG. 63 into a complete stent structure.

FIG. 65 illustrates three stent fabrication panels having an alternativeconstruction corresponding to the stent prosthesis of FIGS. 61, 62A and62B.

FIGS. 66 and 67 illustrate a second alternative stent prosthesisstructure having displacement regions such as circumferentialdisplacement regions present adjacent to axial links adjoining adjacentcircumferential stent rings.

FIG. 68 illustrates a single discontinuity in circumference, forming a“C shaped” open stent.

FIG. 69 illustrates three discontinuities in circumference, formingthree stent strips (stent sections, or stent segments) along the stentlength, while maintaining connection (axial links) between adjacentrings.

FIG. 70 illustrates five discontinuities in circumference, forming fivestent strips (stent sections, or stent segments) along the stent length,while maintaining connections (axial links) between adjacent rings

FIG. 71 shows a stent in a lumen in a relaxed position.

FIG. 72 shows a stent in a lumen in an outwardly flexed position.

FIG. 73 and FIG. 74 illustrate a center section of a stent in betweenadjacent rings.

FIG. 75 illustrates the cyclic nature of the arterial displacement witha stent in place.

FIGS. 76 and 77 illustrate an alternative FEA model run at anothersection of the artery. This section is located near the middle of aring.

FIG. 78 illustrates the cyclic nature of arterial (luminal) displacementat mid-ring and between ring sections.

FIGS. 79 and 80 illustrate a comparison in luminal maximum diameter andluminal area for different stent designs.

FIG. 81 compares radial strengths of modified stents with strength of acontrol stent.

FIGS. 82-83 illustrate a comparison in luminal maximum diameter andluminal area for stents with different number of discontinuities perring, and control stent.

FIG. 84 illustrates an alternative example of a stent prosthesisstructure having displacement regions (separation regions ordiscontinuities) such as circumferential displacement regions present atapproximately 45 degree angles in the crimped configuration.

FIG. 85 illustrates an alternative example of a stent prosthesisstructure having displacement regions (separation regions ordiscontinuities) such as circumferential displacement regions present ina configuration that allows a wider range of alignment.

FIGS. 86A-86C illustrate an example of a prior art stent prosthesiscoupled to a tricuspid valve for placement in an aortic valve annulus toreplace the native aortic valve.

FIGS. 87A-87D illustrate an example of a stent prosthesis for valvereplacement having a sinusoidal pattern showing at least one ring havingfour separation regions, or joints, along the at least one ringcircumferential path. The coupled valve elements are not shown.

FIGS. 88A-88D illustrate an example of a stent prosthesis for valvereplacement (or repair) having a sinusoidal pattern showing at least onering having three separation regions, or joints, clustered along onesegment (or region) of the at least one ring. The coupled valve is notshown.

FIGS. 89A-89D illustrate an example of a stent prosthesis for valvereplacement (or repair) having a closed cell stent pattern withsymmetrically placed separation regions or joints.

FIGS. 90A-90D illustrate an example of a closed cell pattern of stentfor valve replacement (or repair) having a closed cell stent patternwith clustered separation regions or joints.

FIGS. 91A-91E illustrate an example of a fixation implant having atleast one joint allowing a displacement in at least one direction, andchange in shape configuration, after expansion.

FIGS. 92A-92F illustrate an example of a fixation implant having twojoints allowing displacement in at least one direction (or dimension),and change in shape configuration, after expansion.

FIGS. 93A-93E illustrate an example of a fixation implant having twojoints allowing for displacement (or movement) in an axis orthogonal toplane of the hoop.

FIGS. 94A-94B illustrate a fixation implant having three joints allowingfor movement in at least one direction, and change in shapeconfiguration.

FIGS. 95A-95C illustrate a fixation implant having three joints allowingfor movement (or displacement) in at least one direction (or dimension)being in an axis orthogonal to the plane of hoop.

FIGS. 96A-96B illustrate a stent for valve replacement having separationregions (or joints) and having a skirt on the outside of the stenthaving perforations. The stent is coupled to a valve (not shown).

FIGS. 97A-97G illustrate stent crowns having voids with differentgeometries.

FIGS. 98A and 98B illustrate stent crowns, struts, and links havingvoids formed as channels (FIG. 98A) and slots (FIG. 98B).

FIGS. 99A-99C illustrate stent crowns with thinned and/or taperedregions.

FIGS. 100A-100D are OCT images of stents of the present inventionshowing the separation regions forming discontinuities in the scaffoldsof the present invention after implantation in a porcine artery.

FIGS. 101A and 101B are plots of the stents and luminal mean areas forthe test scaffolds of the present invention, and the control scaffolds(not having separation regions), after implantation in a porcine artery.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-3, a conventional endoluminal prosthesis 10comprises a generally tubular scaffold 12 including zig-zag rings 14.Each zig-zag ring 14 includes a plurality of generally straight struts40 joined by curved hinges (expansion regions) 42. As shown in FIG. 2A,where the prosthesis 10 is in a “rolled-out” configuration, the hinges42 are relatively close together and the diameter of the prosthesis isat a small diameter or at a minimum, typically referred to asnon-expanded or “crimped.” As shown in FIG. 2B, in contrast, the stenthas been radially expanded so that the hinges 42 have opened and thestruts 40 have moved circumferentially apart. Such zig-zag stentconstructions are well known in the art in both metallic and polymericmaterials.

FIGS. 3A and 3B illustrate a second type of conventional endoluminalprosthesis commonly referred to as a “serpentine” stent. The serpentinestent or endoluminal prosthesis 16 comprises a circumferential scaffold18 with a plurality of serpentine rings 20. Each ring 20 includes aplurality of generally linear struts 21 joined by curved or bent hinges22. The hinges 22 generally have a larger diameter than those of thehinges 42 in the zig-zag stents, and the struts 21 will generally lieparallel to each other in the non-expanded or crimped configuration ofFIG. 3A, as opposed to slightly offset or the non-parallel orientationof the struts 40 of the zig-zag stent. The serpentine stent 16 furtherincludes a first type of axial link 23 which joins the outermostserpentine rings to the adjacent main body of the circumferentialscaffold. The axial links 23 join the outer diameters of adjacent hinges22 so that the hinges are spaced apart by the full length of the link.Within the main body of the circumferential scaffold 18, however, thelinks 24 are joined from the outer diameter of a first serpentine ring20 to the inner diameter of an adjacent serpentine ring 20. In this way,the hinges 22 are spaced close together but out of phase when the stentis in its crimped or small diameter configuration, as shown in FIG. 3A.When the serpentine stent 16 is balloon or otherwise expanded, as shownin FIG. 3B, the hinges 22 open up and the struts 21 diverge much moregreatly than shown with the struts 40 in the zig-zag endoluminalprosthesis 10. In one example, the angle between two adjacent strutsjoined by an expansion region can range from substantially zero in thecrimped configuration to about 160° or more in the fully expandedconfiguration.

The present invention is directed at methods and structuralmodifications for many types of balloon-expandable and self-expandingendoluminal prosthesis including but not limited to prostheses withzig-zag structures and serpentine structures as just described. Themethods and structural modification are also directed to the varioustypes of stents such as closed ring type, closed cell type, open celltype, helical coil or wire type, wire mesh type, balloon expandabletype, self-expanding type, to name a few, whether formed from wire(s),sheet, or a tube, or other. It is an object of the present invention toprovide prostheses which will, upon implantation or after implantationand/or over time, uncage the body lumen, have a radial strain(compliance) ranging between 1% and 5%, expands and/or contracts in thedeployed configuration ranging from 0.05 mm to 1 mm while havingsufficient strength in the deployed configuration to support a bodylumen, further expand to a larger diameter after inward recoil frominitial expansion, exhibit vaso-constriction and/or vaso-dilation inresponse to a therapeutic agent, decrease resistance to circumferentialexpansion of the stent in order to accommodate luminal remodeling inblood vessels and other body lumens. In some specific embodiments orexamples, the prostheses of the present invention will comprise or becomposed primarily of biodegradable (degradable) polymers, or degradablemetal, which will substantially degrade over time so that they no longerinhibit vessel expansion and remodeling. In such biodegradable stents,the present invention will provide modifications which increase thestrength, or initial strength of the stents so that they can provideadequate structural support for the body lumen during the deployment, orafter deployment, or healing process but limit interference withsubsequent remodeling of the lumen during later stages of the healingprocess. In other examples or embodiments of the present invention, theendoluminal prosthesis will comprise a circumferential scaffold which isformed or fabricated from a high-strength material, such as a metal orhard plastic, which is non-degradable or slowly degradable in theluminal environment. With prostheses having inherently high strength,the present invention will provide for modifications which enable thestent to, break into pieces, or break into segments, or break intopatterned structures, or have separation regions forming discontinuitiesupon deployment, or after deployment, such as during the later stages ofthe healing process so that there is minimum interference with vesselremodeling. In still other embodiments or examples, the endoluminalprostheses of the present invention may be provided with joints such asactive joints which remain intact and provide resistance to vesselcompression while allowing vessel expansion after deployment. In yetother examples or embodiments, the prosthesis of the present inventionmay comprise non-degradable material that provides high radial strength(crush resistance) upon expansion of the stent and the material weakensafter implantation lowering the resistance of the stent to furtherexpand in response to vessel or lumen remodeling.

I. Polymeric or Metallic Prostheses with Reinforcement Elements

Referring now to FIGS. 4-9, endoluminal prostheses of the presentinvention may be patterned from biodegradable polymeric materials (orbiodegradable metallic material) in any conventional stent pattern. Forexample, a serpentine endoluminal prosthesis 16 having a pattern ofstruts 21, hinges 22, and links 23 and 24 may be provided withreinforcement elements 26, as shown in particular in FIGS. 4A and 4B. InFIG. 4A the prosthesis is in its crimped or small diameterconfiguration, and a first type of reinforcement element 26, typicallyformed as a curve or crescent, but can have various shapes, sizes, andgeometries, is provided in selected ones of the hinges 22. It isparticularly desirable to provide the reinforcement within the hinges asthe hinges will be stressed during opening of the stent, as shown inFIG. 4B, and reinforcement will help the expanded hinges resist yieldingto compressive forces which may be present after the initial expansionin the blood vessel or other body lumen.

The reinforcement elements do not, however, need to be limited to thehinge regions 22 and may extend generally along two, three, four, ormore contiguous hinges 22 and struts 24, as shown with reinforcementelements 28 in FIGS. 4A and 4B.

The reinforcement elements 26 and 28 will often be malleable, typicallybeing formed from a malleable metal or metal alloy, and may be embeddedor otherwise coupled or attached within the body of the hinge, strut, orin some cases links. In other cases, the reinforcement elements 26 and28 could be formed from a resilient metal, such as a shape memory alloyor a spring stainless steel. In such cases, the reinforcement element 26or 28 will typically be in a constrained configuration when the stent isin its closed pattern, as shown in FIG. 4A, such that the reinforcementelement 22 or 28 will be biased to promote opening of the hinges 22 andthe circumferential scaffold 18, as shown in FIG. 4B. Often, thereinforcement elements 26 and 28 will remain biased (partially closed)even when the scaffold is in a fully or partially expanded pattern, asshown in FIG. 4B, so that the biased hinges can continue promotingopening of the stent to accommodate luminal remodeling during the laterstages of the healing process. The shape memory or spring reinforcementelements can be coupled to expansion regions, and/or coupled to twoadjacent struts (as an expansion region/hinge), where such reinforcementelements can further expand the stent after implantation of the stent(after deployment) and before substantial degradation of the stent, orfurther expand the stent after implantation and before completedegradation of the stent, or further expansion of the stent afterimplantation. The amount of further expansion of the stent is controlledby the number of reinforcement elements, and opening angle suchreinforcement elements are programmed to open to, the vessel or lumenresistance to the reinforcement elements opening, the resistance thedegradable material coupled to the reinforcement elements provides atthe time. Typically, such shape memory or spring material can furtherincrease the stent diameter after implantation by 0.05 mm to 0.5 mm.

As shown in FIGS. 5A and 5B, reinforcement elements 30 may be placed ina serpentine endoprosthesis 16 so that they extend across axial links 24in addition to struts 21 and hinges 22. In this way, the reinforcementelement 30 will span both the circumference and the axial length of thescaffold 18.

As shown in FIGS. 6A and 6B, reinforcement elements 32 extendsubstantially around an entire serpentine ring 20 with only or at leasta single break or other discontinuity 33 in the circumference of thereinforcement element. In this way, a maximum of reinforcement isprovided to the serpentine ring 20 while the remaining opening or gap 33allows the reinforcement (which generally will not degrade or notdegrade as quickly as the biodegradable material) to open and avoidcaging or jailing the body lumen as the body lumen is in the laterstages of the healing process. The opposite ends of the reinforcementelement in the break region are either in contact or are apart (as shownin FIGS. 6A and 6B). The distance of the break region between the endsof the reinforcement elements often can range from 5 microns to 1 mm,typically ranges from 10 microns to 0.5 mm, more typically ranges from15 microns to 0.2 mm. The ends of the reinforcement elements can bedeburred, rounded, made into a ball, or configured into other shape,geometry, or size, in order to minimize trauma to the vessel wall.

Referring now to FIGS. 7A and 7B, box-shaped reinforcement elements 34may be provided to cover struts 21, hinges 22, and links 24 to provideboth strong support and to leave structures, patterned structures, orrelatively large structures behind after the biodegradable stentmaterial has degraded. An advantage of such relatively large boxstructures is that they will not be inadvertently lost in the bloodcirculation after the biodegradable circumferential scaffold 18 hasdegraded or disappeared, and/or can provide luminal support after thestent has degraded.

As shown in FIGS. 8A and 8B, reinforcement elements 36 need not beembedded within the structure of the circumferential scaffold 18 andneed not even follow the pattern of the struts 21 and hinges 22. Thereinforcement elements 36 are external to the circumferential scaffold18 and coupled or attach to the struts and hinges only at selectedlocations, as shown in more detail in the example of FIG. 9Dhereinafter.

Referring now to FIG. 9A, a metal or other reinforcement element 26 maybe coupled to a hinge 22 by embedding or otherwise attaching the elementinto the hinge body, as described with greater particularity below.While illustrated with the short reinforcement elements 26 embedded inhinges 22 as shown in FIGS. 4A and 4B, it will be appreciated that suchtechniques for embedding reinforcement elements into a hinge will alsoapply to embedding such reinforcement elements into struts, axial links,or any other components of a biodegradable circumferential scaffold.

Referring now to FIG. 9B, in other instances which are sometimespreferred, the reinforcement element 26 may be formed as a rod and maybe fully embedded into a hinge 22 so that no portion of thereinforcement element is visible on the surface of the hinge.

As illustrated in FIG. 9C, a reinforcement element 26 may be surfacemounted on a hinge 22 or any other portion of a biodegradable polymericor biodegradable metallic circumferential scaffold. Reinforcementelements may be surface mounted onto hinges, struts, links, and othercomponents of a polymeric biodegradable circumferential scaffold, ormetallic biodegradable stent.

Referring now to FIG. 9D, the external reinforcement elements 36illustrated in FIGS. 8A and 8B may be attached to struts 21, hinges 22,or other components of the biodegradable circumferential scaffold 18 byattaching with pins 38 for example. As illustrated, one pin 38 isattached at each end of the external reinforcement element 36, butadditional pins could be added at intermediate locations where thereinforcement element crosses over a strut 21 or hinge 22.

In one example, grooves, fissures, slots, are formed in the polymeric ormetallic material, where the reinforcement material is then pressfitted, fitted, and/or inserted into said grooves, slots, fissures. Inanother example separately or in addition from the previous example, acoating, an adhesive, or other bonding, holding, filling, or removinggaps means are added to the polymeric material (or metallic material)and/or reinforcement material to hold, fill, or affix the metallic orpolymeric frame (main polymer material) and the reinforcement materialtogether. In another example, the reinforcement material is heated to atemperature above the melting temperature of the polymeric material tobe coupled with and then press fitted onto or into the polymericmaterial. In yet another example, the polymeric material is treated witha solvent to soften (or partially melted or partially dissolved) thepolymeric material and then inserting or fitting the reinforcementmaterial onto or into the softened (or partially melted) polymericmaterial. In another example the reinforcement material is sandwichedbetween polymeric material layers (formed by dipping, spraying, molding,and/or extruding the reinforcement material with the degradablepolymeric material), wherein the reinforcement material either has gaps,and/or discontinuities, before patterning the tubular structurecomprising the polymeric material and the reinforcement material, orsuch gaps and/or discontinuities are formed after or during patterningthe tubular structure. Once the tubular structure is patterned,additional polymer, adhesive, or other means can be applied to holdtogether the patterned structure.

II. Non-Degradable or Degradable (Having High Initial Strength UponExpansion) Prosthesis Having Rings with Separation Regions,Environmentally-Responsive and/or Energy-Responsive Separation Regions

Referring now to FIG. 10, an expandable zig-zag showing partial ring 14is illustrated in detail with a plurality of struts 40 joined by hinges42 and adjacent rings attached to each other by axial links 44. For thepurposes of the following discussions and examples, the zig-zag ring 14is formed from a metal or other non-degradable material (but it can alsobe formed from a degradable material such as metallic or polymericmaterial having high stiffness upon expansion of the stent), where thematerial will be modified at particular locations or regions to weakenthe material (or to form a junction) so that it will formdiscontinuities or separations at those locations (separation regions)or in those regions over time and/or after expansion. In some cases, thediscontinuities or dislocations will occur as a result of the luminalenvironment in which the prosthesis has been implanted. For example,when implanted in vasculature, the blood vessels will naturally pulsateproviding a continuous mechanical stress to the endoluminal prosthesis,or a valve annulus contracting and expanding (or dilating) duringbeating of the heart. By modifying the physical properties of thecircumferential scaffold at particular locations or separation regions,those locations will preferentially break (coming apart, and/orseparation) over time, allowing the circumferential scaffold to uncageand/or further expand after deployment and/or after it has becomeincorporated into the vessel wall. In this way, undesirable caging orjailing of the blood vessel, or other body lumen, or the stented segmentcan be prevented. In other instances, the preferential breaking ofcertain locations or separation regions on the circumferential scaffoldcan be induced or enhanced by the application of external energy fromany one of a variety of sources, including magnetism, ultrasound energy,heat, radio frequency energy, subsequent therapeutic drug such as avaso-dilator or vaso constrictor, balloon expansion within the bodylumen, or the like. In the following discussion, it should beappreciated that most or all of the particular structural or physicalmodifications to the circumferential scaffold could be configured oradapted to be responsive to either a physiologic environment within thebody lumen and/or to the application of external energy.

Referring now to FIGS. 11A and 11B, a first structural modificationcomprises notches 46 formed within a hinge 42 joining a pair of adjacentstruts 40. In the crimped diameter configuration, as shown in FIG. 11A,the V-shaped notches 46 are open at a relatively large angle. After thecircumferential scaffold is expanded, such as by balloon expansion, thenotch 46 will partially close as shown in FIG. 11B. By leaving aremaining albeit smaller opening in the notch 46, as the circumferentialscaffold repeatedly expands and contracts due to the luminal pulsation,the remaining attached portion of the hinge will act as a “living hinge”which is subjected to concentrated stress that will cause it to breakover time. By properly selecting the amount of material which is left inthe hinge 42, an expected lifetime for the hinge can be selected orprogrammed. Thus, a particular endoluminal prosthesis may be fabricatedwith a predictable life expectancy for remaining intact within the bloodvessel or other body lumen but opening after expansion, typically afterthe body lumen has healed a sufficient amount and it is no longernecessary to have support from the intact scaffold. While primarilyintended for being responsive to the mechanical pulsations of the bloodvessel or other body lumen, or simulated pulsation ex-vivo, it will beappreciated that the weakening of the hinge 42 by a notch 46, as shownin FIGS. 11A and 11B, would also render the hinge more susceptible tofatigue or erosion from other conditions of the physiologic environmentin the body lumen and/or the application of external energy, and/orbreakage.

As an alternative or in addition to placing notches 46 in the hingeregions of a circumferential scaffold, notches 48 may be placed in thestruts, beams or other generally non-deformable regions of thecircumferential scaffold, as illustrated in FIGS. 12A and 12B. Thestruts 40 will also be subjected to stresses from the endoluminalenvironment, and can be programmed to break in response luminalpulsations over time.

Referring now to FIGS. 13A and 13B. Notches 50 may also be placedadjacent to (as shown) the axial links 44 adjoining hinge regions 42 ofthe circumferential scaffold. The hinges 42 adjacent to axial links 44would fatigue or erode at a pre-programmed approximate duration inphysiological environment or be subjected to even greater stresses thannotches in the other hinge regions, so these locations may providealternative capabilities for programming the stent breaking. Also, inaddition to releasing the rings 14 to expand radially and/or uncage,opening the scaffolds on the crowns, struts, and adjacent to the links44 (on the crowns) would enhance the circumferential opening of thescaffolds. It can be appreciated that such notches, grooves, or otherfeatures, in these figures and examples can be coated with a material orcontained with a sleeve, such as a polymeric material, where the coatingor the sleeve would help protect the vessel wall from any atraumaticcomponents of such notches when they break. The sleeve or coating can benon-degradable or degradable, where in the preferred example thedegradable coating or sleeve would degrade after the ring breaks. In thecase of the non-degradable material such as paralyne, it would containthe notches after the notches break. In either case, the coating and/orthe sleeve would allow the ring or circumferential structural element touncaged, or be able to move at least in a radial, circumferential,and/or longitudinal direction.

Referring now to FIGS. 14A and 14B, shows two serpentine rings 52 and54, each ring contains two partial rings forming a separation region 56between their adjacent struts. The separation region 56 extends betweenthe two adjacent rings 52 and 54 which completely separates each of thetwo partial rings on ring 52 and ring 54 except for a region such as acenter region 62 which remains attached or held together. As the rings52 and 54 are radially expanded, the separation region opens so thatfour segments 56 a, 56 b, 56 c, and 56 d open to form a pattern such asX-pattern, as shown in FIG. 14B. The partial rings of 52 and partialrings of 54 remain held together by only the center section 62 in thisexample which can be configured to break, completely separating the twoadjacent partial rings of 52 and completely separating the two adjacentpartial rings of ring 54, after a desirable time period or afterdeployment. In particular, the width and thickness of the center portioncan be chosen to break or separate in response to pulsation stresses,other intraluminal conditions, and/or the application of external energyand combinations thereof. Typically, the breakage of the center section62 will not form a discontinuity in rings 52 and 54 without the presenceof separation regions between the two partial rings of 52 and betweenthe two partial rings 54.

Referring now to FIGS. 15A and 15B, the properties of the material suchas the metal in the hinge regions 42 (but can also be in other regionssuch as struts) may be modified to weaken these separation regions sothat they break or separate or form a discontinuity after apredetermined time in the endoluminal environment and/or after exposureto external energy. For example, the grain boundaries within the hingeregions can be modified to provide such programmed breaking orseparation. The grain boundaries can be modified, for example, byannealing the material at a high temperature to modifying the grain sizeand rendering the annealed area weaker and prone to break within adesire time period. As discussed, a sleeve, or a coating can be placedover at least a portion of the region to contain the at least part ofthe hinge region until breakage of said region, or until a longer timeafter breakage.

Referring now to FIGS. 16A through 16D, non-degradable circumferentialscaffolds structural elements (but can also be degradable material suchas metal or metal alloy having high initial strength upon expansion)such as crowns, struts, or other, can be pre-cut, or patterned as shown,or separated and then rejoined, and/or held together so that they remainintact during deployment of the endoluminal prosthesis and for a desiredperiod of time thereafter. By properly choosing how the cut/severed(separation region discontinuities) ends of the scaffold component arerejoined, breaking (separation, gap formation, unlocking, and/orbreaking apart, discontinuities) of these regions can be achieved withinselected time periods as described throughout the application. Forexample, as shown in FIG. 16A, a butt joint 68 may be formed by cuttinga strut 40 at a location and then rejoining the ends of the joint, forexample, using an adhesive or a polymer. The adhesive can be chosen toremain intact for a desirable initial period but to break after thattime has elapsed.

As an alternative or in addition to an adhesive, a biodegradable sleeve70 may be placed around the severed location in the strut 40. Thebiodegradable sleeve may be formed from a polymeric or other materialwhich degrades over time in response to the luminal environment and/ordegrades in response to the application of external energy, forming adiscontinuity, and uncaging the adjacent ring of the structural element.The sleeve may also be non-degradable but allows for movement of thestructural elements (including the ends) in one or more directions suchas the radial, circumferential, and longitudinal direction, afterexpansion. The sleeve in this case can be stretchable, deteriorates atleast partially, or loosens, to allow for movement of the structuralelements ends.

As shown in FIG. 16C, a key and lock junction 72 may be formed in twoadjoining segments of a strut 50. The key and lock may then be held inplace by an adhesive, sleeve, cement or polymer 74, either an adhesive,polymeric material, or other substance which will degrade within theendoluminal environment over a predetermined time, and/or erode by theapplication of an external energy. In another example, the key and lockare tightly fit (or substantially tightly fit) not requiring an adhesiveor a polymer for the adjoining segments to function or to be heldtogether for expansion of the stent and having sufficient strength tosupport a body lumen. The tight fit end will eventually separate,particularly in response to vessel pulsation, preferably in the radialdirection, but can also move circumferentially and/or eventually move ina longitudinal direction.

As yet another alternative shown in FIG. 16D, a rivet 76 may be formedto join adjacent segments of a strut 40. For example, the ends of thestruts may be formed to have overlapping elements 77 and the rivetplaced there through. The rivet can be formed from any of thebiodegradable materials discussed herein which erode (includes degradeor corrode) over time.

Referring now to FIGS. 16E-1 through FIG. 16E-3, a further exemplary“key and lock” separation region 80 includes a first strut segment 81and a second strut segment 82. The key and lock separation region 80 isformed by an enlarged head 83 formed at one end of the first strutsegment 81 and a slot or receptacle region 84 formed at one end of thesecond strut segment 82. The enlarged head 83 and slot receptacle region84 are detachably joined in a manner similar to pieces of a “jigsaw”puzzle where the enlarged head 81 may be formed or patterned in thisconfiguration or pressed into the slot or receptacle region 84, and onceso joined, the strut segments 81 and 82 may not be axially pulled apart.They may be separated preferably only be a relative “vertical” or radialmovement as shown by the arrows in FIG. 16E-3.

Conveniently, the enlarged head 83 and the slot or receptacle region 84may be formed in the strut segments 81 and 82 by laser cutting of a tubewhile the rest of the scaffold structure of the stent or other luminalprostheses is being fabricated. A physical break or discontinuitybetween the enlarged head 83 and the slot or receptacle 84 will usuallybe formed as a single cut line so that a minimum of material is removedfrom the resulting prosthesis structure. Alternatively, additionalmaterial could be removed (by multiple curt lines) so long as preferablyan interference fit remains between the enlarged head 83 and the slot orreceptacle region 84 so that axial separation is inhibited under axialtension.

After the individual struts 81 and 82 are cut from the starting tube,and the cut line or space which separates the enlarged head 83 from theslot or receptacle region 84 is formed, the resulting free ends of thestrut segments 81 and 82 will usually be temporarily immobilized so thatthey cannot be vertically displaced relative to each other to inhibitopening of the joint during deployment and enlargement (expansion) ofthe prosthesis. For example, the enlarged head 83 and slot or receptacleregion 84 may be joined with an adhesive or polymer which is introducedinto and typically fills the gap or region between the head and slot. Inparticular, the adhesive or glue or polymer will typically act to jointhe adjacent, abutting surfaces of the head 83 and the slot 84 togetherto inhibit any shear motion there between. The adhesive or polymer willusually be biodegradable so that it will degrade over time as set forthelsewhere in the present application in order to free the ends of thestent segments to permit the vertical motion/movement illustrated inFIG. 16E-3 but it can also be non-degradable yet allowing the uncagingof the scaffold or permitting vertical or radial or circumferentialmovement. Alternatively or additionally, the enlarged head 83 and slotor receptacle region 84 may be immobilized by circumscribing orencapsulating the head and slot region with a biodegradable sleeve 85,shown in broken line in FIG. 16E-2. The slot receptacle in these figurescan also be configured to open up after expansion of the stent allowingthe enlarged head to move in a longitudinal direction and/or radialdirection. The slot receptacles can open as a result of physiologicconditions such as the pulsation of the heart or material fatigue. Theslot receptacles can be configured in one example to have substantiallysmall width around the enlarged head facilitating the opening of theslot receptacle in a pulsating environment or movement.

The biodegradable sleeve 85 can be formed over the cut line, space orother break in the strut by extrusion, spraying, dipcoating, brushing,molding, or the like, or combinations thereof. Suitable materials forsleeve, cement, polymers, adhesives, are described throughout thisapplication, and/or include but are not limited to: lactides,caprolactones, trimethylene carbonate, and/or glycolides such aspolylactide, poly(L-lactide), poly-DL-Lactide, polylactide-co-glycolide(e.g., poly(L-lactide-co-glycolide) with 85% L-lactide to 15%glycolide), copolymer of poly(L-lactide-co-epsilon-caprolactone (e.g.,weight ratio of from around 50 to around 95% L-lactide to about 50 toabout 5% caprolactone; poly (L-lactide-co-trimethylene carbonate),polytrimethylene carbonate, poly(glycolide-trimethylene carbonate),poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids; protein such as elastin, fibrin, collagen,glycoproteins, gelatin, or pectin; poly-serine; polycaprolactam;cyclodextrins; polysaccharides such as chitosan, and hyaluronan;alginate; polyketals; fatty acid-based polyanhydrides, amino acid-basedpolyanhydrides; poly(ester anhydride); or combinations thereof.

A further exemplary “key and lock” separation region 87 is illustratedin FIGS. 16F-1 through 16F-4. The key and lock region 87 joins a firststrut segment 88 and a second strut segment 89. In contrast to the keyand lock separation region 80 preferred separation direction, the keyand lock separation region 87 allows separation of the strut segments 88and 89 in both a relative vertical direction, as shown by the arrows inFIG. 16F-3, and in a relative axial direction as shown by the arrows inFIG. 16F-4. Such different performance in one example results from thetongue 90 not having an enlarged profile relative to the slot 91. Inthat way, the tongue 90 and slot 91 are able to freely move eitheraxially or vertically relative to each other.

As with the key and lock separation region 80, however, the key and lockregion 87 will also be immobilized so that it is stabilized duringimplantation and/or expansion of the prosthesis of which it forms apart. The immobilization may be using an adhesive, polymer, or using asleeve 92, both of which are described in more detail elsewhere herein.Also, other means to hold the region can include grooves, hooks, orother features on the surfaces of the strut segments to create frictionand/or fixation, as the stent expands from a crimped configuration to anexpanded larger configuration.

Mobility in both the vertical and axial directions as provided byseparation regions 87 and 95 (after sleeve or adhesive degradation) isbeneficial as it maximizes the ability of the stent to radially enlargeafter implantation. Mobility in the axial direction, however, increasesthe chance that the separation region will separate as the stent isradially expanded by the delivery catheter or other means, e.g. thesleeve 92 or 99 will be less able to hold the adjacent strut segmentstogether under tension than under shear in this example. In contrast,separation regions with preferably radial or circumferential mobility,such as separation region 80, will be better able to resist separationforces while the stent is being radially expanded but will be somewhatless free to allow stent expansion after the sleeve degrades. Usually,however, both designs will allow separation in response to tissue andvessel contractions after the sleeve degrades or has been degraded.

Both key and lock regions 80 and 87 will be preferably incorporated intoa linear or about the middle region of strut (but can be positioned onany location of the strut) of a type for example which are joined bycrowns in serpentine or zig-zag stent patterns or other stent designtypes, as shown for example in FIG. 16F-5 showing a serpentine pattern.The stent pattern shown in FIG. 16F-5 includes a plurality ofcircumferential rings 93 comprising strut elements 94 a (which may ormay not include a key and lock separation region), joined by crowns 94b. Axially adjacent serpentine rings 93 are joined by axial links 94 cwhich are disposed between adjacent crown regions 94 b. On the specificexample illustrated in FIG. 16F-5, the circumferential rings 93 eachinclude two or three key and lock separation regions 87. The samepattern of key and lock separation regions, however, could also utilizethe key and lock regions 80 described above, or the key and lock regions95 described herein below, or other types or patterns of separationregions. The stent pattern illustrated in FIG. 16F-5 is shown in a“rolled-out” configuration so that it appears flat and is easier toobserve. The actual stent cutting pattern, however, will typically bedrawn on a tubular structure which is then laser cut into the desiredpattern, or the pattern can also be formed starting with a wire or coiland patterned into a stent. The rings of FIG. 16F-5 example show all therings having separation regions (2 or 3 separation regions per ring) ina specific pattern. The separation regions are held together uponexpansion of the stent from a crimped configuration to an expandedlarger configuration, and allow the stent in the expanded configurationto have sufficient strength to support a body lumen. The separationregions form discontinuities after expansion, usually from 30 days to 1year, preferably from 3 months to 9 months, but can also sometimes formdiscontinuities immediately after expansion of the stent provided thatsuch separation regions in one example allow the stent to havesufficient strength to support a body lumen, the separation regions canbe configured to form discontinuities about the same time, or formdiscontinuities at different times utilizing various methods comprisingfor example the amount (or thickness) of the material holding suchseparation regions together, the degradation time of the materialholding the separation region together, the type and properties of thematerial holding the separation region together, and the location andnumber of the separation regions on the ring, controlling the separationforce on the separation regions, the magnitude and frequency of stresseson the separation regions, the dimensions, angles, and thickness, of thestructural element where the separation region is on, and/or theadjacent crown and/or adjacent struts, and the location of separationregion on said crown region or strut region, or other. Each ring in thisexample FIG. 16F-5 uncages when at least one separation region in eachring forms a discontinuity. It is desirable sometimes to have multipleseparation regions on each ring or on at least some rings in order todistribute more uniformly the stresses on the ring after formation ofthe separation regions, and/or provide for a larger uncaging magnitude.Stent types include closed ring type, closed cell type, open cell type,helical coil or wire type, wire mesh type, balloon expandable type,self-expanding type, to name a few, whether formed from wire(s), sheet,or a tube, or other. In some of the stent types such as some closed celltype designs for example diamond shaped closed cell design, it isnecessary to have at least two separation regions per cell or ring touncage such ring (in order to create a discontinuity in thecircumferential path of said ring), or in other examples it might benecessary to have at least three separation regions per cell or ring touncage such ring ((by creating at least one discontinuity in thecircumferential path of said ring provided that such at least onediscontinuity uncages said ring, otherwise at least one morediscontinuity is required to uncage the ring, and so forth, untilsufficient number and locations of discontinuities are sufficient touncage said ring). Some closed cell type designs for example somediamond shape type have a circumferential connector (such as strut,crown, or adjacent to strut or crown regions) linking adjacent closedcells on the same ring. Having a separation region on saidcircumferential connector forms a discontinuity in such circumferentialconnector would uncage the ring, or having two separation regions on thediamond closed cell would uncage the ring by providing at least onebreak in the ring circumferential closed path. This can also apply toopen cell design having a plurality of adjacent rings, where adjacentrings are joined (or linked) by a circumferential connector (a connectorextending circumferentially in the crimped and/or expanded configurationof the stent), typically such connector is in the crown region oradjacent to the crown region. Having one or more separation regions onsaid circumferential connector forms a discontinuity in suchcircumferential strut, and would uncage the ring. FIG. 16F-5 also showstwo links connecting two adjacent rings. It is desirable to have thenumber of axial links be less than the number of crowns per ring, it ismore desirable to have the number of the axial links be ⅓ or less thenumber of crowns for improving axial flexibility of the stent. It isalso desirable to have at least one link joining two adjacent rings (orat least one crown region on one ring is joined to an adjacent crownregion on an adjacent rings) to remain intact after the separationregions form discontinuities so that the stent structure (or part of thestent structure) is held together (or remain intact) in at leastlongitudinal direction. It is more desirable to have at least two linksjoining two adjacent rings (or at least two crown regions on one ring bejoined to two adjacent crown regions on an adjacent rings) to remainintact after the separation regions form discontinuities so that thestent structure (or part of the stent structure) is held together in alongitudinal. Having at least two axial links is desired to minimizefish-scaling and/or crown collisions. It is desirable to have the stentstructure be held together (or remain intact) in the axial direction forat least some adjacent rings after formation of discontinuities (afteruncaging circumferentially of the stent) while (or by) having at leastone link connecting every two adjacent rings of said at least someadjacent rings, or while (or by) having at least two links connectingevery two adjacent rings of said at least some adjacent rings, remainintact, or while (or by) having substantially all axial links connectingevery adjacent rings of said at least some adjacent rings, remainintact. This (having at least part of the stent be axially connected,preferably the entire length of the stent be axially connected) wouldhelp provide support to the body lumen (or vessel), and preventpotential dislodgement of the structural elements into the blood stream.In some examples, at least some but not all separation regions on atleast some rings remain held together (in place) and not separate,without affecting the uncaging of said rings as a result of having otherseparating regions on said rings separate creating at least onediscontinuity along the circumferential path of each of said rings.

Referring now to FIGS. 16G-1 through 16G-3, a further example of a keyand lock separation region 95 is illustrated. The key and lockseparation region 95 is similar to the key and lock separation region 87except that the tongue 97 on first strut segment 96 a is significantlylonger than the tongue 90 on strut segment 88. For example, the tongue90 will typically have a length in the range from 0.15 mm to 0.90 mm,usually from 0.3 mm to 0.70 mm, while the tongue 97 will have a lengthin the range from 0.3 mm to 2 mm, usually from 0.4 mm to 0.9 mm. Thecorresponding slot 98 at an end of a second strut 96 b will usually havea length which matches that of the tongue 97, but in some examples couldbe longer to allow a gap or open region within the slot when the stentor other prosthesis is fully assembled. As with the key and lockseparation region 87, the key and lock region 95 allows separation inboth an axial direction and a vertical or radial or circumferentialdirection, as indicated by the arrows in FIG. 16G-2. The tongue 97 andslot 98 may be immobilized or held together using either adhesives,polymer, or an external sleeve 99, as generally described with the keyand lock separation regions 80 and 87, above. A stent 150 having the keyand lock separation regions 95 is illustrated in FIG. 16G-3. The patternof the key and lock separation regions 95 within individual struts 152is generally similar as that shown for the stent in FIG. 16F-5, above.

The longer key and lock (or tongue and slot) elements of FIGS. 16G-1 to16G-3 are advantageous as it provides for a larger surface area foradhesion or friction to prevent premature separation than does a shortersegment. Such elongated elements also protect the key/tongue fromdamaging the adjacent tissue during separation. In contrast, a shorterkey and lock separation region can sometimes prematurely separate, andduring fabrication a gap may form between the key (tongue) and lock(slot) before application of adhesive or sleeve, making it moredifficult to adhere, requiring a greater fabrication. The shorter tongueand slot segment has less material than the longer segment so it islighter and more mobile or flexible. The shorter tongue can have athicker coating or sleeve to hold the separation region together, forexample the sleeve thickness on top of the separation region can rangefrom 10 microns to 50 microns, while the thickness of the sleeve on topof the separation region having longer tongue can be thinner rangingfrom 5 microns to 20 microns.

FIG. 16G-4 through FIGS. 16G-6 illustrate scaffold designs exampleswhich allow full opening or unrolling along at least one axiallycontinuous separation regions line (or path) of the stent length asshown in the black line(s). The figures also illustrate examples whichallow opening (or unzipping) along axially continuous separation regionsline (or path) of partial stent length comprising at least three rings.In other example the separation regions can be configured (by selectinga certain arrangement of separation regions, controlling the number ofseparation regions, and choosing the appropriate location of separationregions in relationship to the location of axial links connecting thesame ring and/or adjacent rings) to allow opening (or unzipping) alongaxially continuous separation regions line (or path) of at least part ofthe stent length comprising at least two rings or more, or yet inanother example comprising at least one ring or more. The axial links inmany of the example maintain the structural intactness of the stent (atleast two or more rings of the stent, preferably substantially all ringsof the stent) in a longitudinal direction. Similarly, closed cell typedesigns for example can be configured to achieve a similar result.

As shown in FIGS. 16G-4, a scaffold 600 has separation regions 602formed in circumferential rings 604 having struts 606 joined by crowns608. Adjacent circumferential rings 604 are joined by axial links shownin boxes 612. One separation region 602′ in each ring 604 in thisexample is positioned between adjacent axial links (shown in boxes 612)so that the separation regions lie along a continuous, irregularseparation line 614 that does not go outside of the path between thecircumferentially adjacent “boxed” separation regions. The figure alsoshows an example of the locations of separation regions on the struts(but can also apply to crowns) in relationship to crowns connected toaxial links. In one example the separation region on a strut between (orconnecting) two crowns on the same ring where one or both crowns areconnected to adjacent rings by axial links, or in another example asshown in the figure where the separation region on a strut between (orconnecting) two crowns on the same ring where neither one of the crownsis connected to an axial link. To be clear, the illustrated boxes arenot part of the scaffold structure and are shown only to indicate atleast one path for which of the adjacent separation regions define theaxial separation path along the stent length.

As shown in FIGS. 16G-5, a scaffold 700 has separation regions 702formed in circumferential rings 704 having struts 706 joined by crowns708. Adjacent circumferential rings 704 are joined by axial links 710.In contrast to the scaffold 600 which opens along a single axial line(path) along the entire stent length 614 to form a “C-shaped” crosssection after formation of discontinuities in the separation regions,the scaffold 700 will open along three axial separation lines 714 (orpaths) along the entire stent length because each ring 704 has threeseparation regions 702 and all of the separation rings arranged alongthe lines 714 which line between axially adjacent axial links 710. Thus,after the separation regions 702 have all separated post-implantation,the scaffold will consist of three separate connected axial strips(sections or segments) of partial rings which are not structurallyconnected to each other after formation of discontinuities. The stentshown in FIG. 16G-5 can also have additional multiple shorter connectedaxial sections (or strips) on some rings by having separation regions onall axial links joining the at least some rings but maintaining axiallinks on at least two adjacent rings.

The scaffolds 600 and 700 will separate along generally axial lines,although as is the case with scaffold 600, the lines may meander in somecases. In other cases, as shown in FIG. 16G-6, a scaffold 800 may haveseparation regions 802 arranged in circumferential rings 804 to allowthe scaffold to open along three helical or spiral separation lines (orpaths) 814. Scaffold 800 includes struts 806 joined by crowns 808, andadjacent circumferential rings 804 are joined by axial links 810. Whilethe separation lines appear to be linear in FIG. 16G-6, which is becausethe view has been rolled out along a spiral cut line. Thus, when thescaffold pattern is rolled back into its tubular form, the separationlines 814 will be three parallel spirals or helices formed over the tubeor stent structure. Other scaffold having only a single (or two or fouror more) straight, spiral or helical, or other regular or irregularpatterns or geometries of separation line (path) along the stent axiallength or part of the stent axial length, can also be fabricated byconfiguring the appropriate stent ring pattern, the appropriate numberof links joining rings, the appropriate number of separation regions andlocations within rings, and/or realigning the position of axial links tothe separation regions locations on rings, to achieve the desiredpattern and number of section (or strips) that the stent unzips intoafter uncaging.

Referring now to FIGS. 16G-7A and 7B, a scaffold 1000 has a plurality ofseparation regions 1002 formed in circumferential rings 1004 of thescaffold. As with previous examples, at least some of the rings 1004 ofthe scaffold may be formed from struts 1006 connected by crowns 1008.The separation regions are shown to be key-and-lock junctions, asdescribed previously, but the patterns disclosed in the following FIGS.16G-7A through 16G-10 may apply to any type of separation regiondescribed herein. The separation regions 1002 are shown in their closedor partially closed configuration in FIG. 16G-7A and in their partiallyopened or axially separated configurations in FIG. 16G-7B whichillustrates the scaffold 1000 in its circumferentially expandedconfiguration.

As shown in FIG. 16G-7B, upon expansion of the scaffold 1000, theseparation regions 1002 follow the meandering paths illustrated bybroken lines 1010, 1012, and 1014. segments 1016, 1018, and 1020 thusform in the scaffold upon circumferential expansion, typically byballoon as described elsewhere herein. The segments are held together bylinks 1008 which are circled in FIG. 16G-7B. It should be appreciated,however, that different separation and segmentation patterns can beprogrammed into the scaffold depending on the separation patterndesired. Different available separation patterns examples are discussedbelow with regard to different figures.

As shown in FIGS. 16G-8A and 8B, a scaffold 1030 comprises separationregions 1032, circumferential rings 1034, struts 136, crowns 138, andaxially links 144 connecting adjacent rings. While these basiccomponents are the same as for scaffold 1000, the arrangement ofseparation regions 1032, and axially links 1044 connecting adjacentrings, are selected so that, upon circumferential expansion or aftercircumferential expansion as shown in FIG. 16G-8B, a helical separationboundary 1040 will form about the scaffold to form a single helicalstructural segment 1042 which remain intact (held together by thecircled axial links in FIG. 16G-8B) after expansion and after uncagingin a circumferential direction. In the scaffold 1030, both theseparation regions 1032, and the axially links 1044 connecting adjacentrings, are arranged in complementary helical patterns to insure both thehelical separation and the remaining helical connection of the stentelements after radial expansion.

Referring now to FIGS. 16G-9A and 9B, a scaffold 1050 comprises rings1054 each having a single separation region 1052 formed therein. Therings 1054 are formed from struts 1056 and crowns 1058, and three axiallinks 1060 are formed between each adjacent pair of circumferentialrings 1054, as best seen in the circled regions of FIG. 16G-9B. Thisparticular pattern of separation regions 1052, and axially links 1060connecting adjacent rings, allow the scaffold 1050 to circumferentiallyexpand while all elements of the scaffold remain interconnected so thatthere are no discrete separated segments (no unzipping along the axiallength of the stent) formed after expansion. However, each ring uncagesby forming at least one discontinuity in the circumferential path ofeach ring, thus uncaging the stent.

Stents tend to have low radial strain (compliance) in the expandedconfiguration specially ones that are plastically deformable, such asnon-degradable metals and metal alloys, such as stainless steel alloys,cobalt chrome alloys, and platinum iridium alloys. This may be harmfulto the anatomy the stent is implanted in as it can cause irritation tothe lumen or vessel, it can cause fatigue of the stent or of the lumenor vessel over time as a result of having a substantially rigidstructure in a dynamically (or constantly) moving environment, and canresult in adverse events over time. Typical % radial strain (compliance)approximation for coronary artery ranges from 3% to 5%. Stenttechnologies, when expanded in a lumen (or mock tube), tend to have %radial strain (composite compliance) usually between 0.1% and 0.5%,typically in the range from 0.1% to 0.3%. It is an objective of thisinvention to configure a stent, in accordance with the presentinvention, to having % radial strain (or composite compliance) rangingfrom 0.5% to 5%, preferably ranging from 1% to 5%, more preferablyranging between 1% and 5%, most preferably from 1.2% to 5%, or from 1.5%to 5%, after expansion of the stent prosthesis from a crimpedconfiguration to an expanded configuration, or after formation ofcircumferential discontinuities, when the inner stent diameter isexpanded within a lumen (or mock tube) to approximately 110% the innerdiameter of the lumen (or mock tube) under physiologic condition, andwhere the lumen (or mock tube) has a compliance ranging from 4% to 5%,or the stent of the present invention after expansion in a body lumen(or mock tube) would have a substantially similar radial strain (orcomposite compliance) to that of the anatomy the stent is implanted in,or the stent of the present invention is configured to have a compositecompliance of at least 25% of that of the radial strain (compliance) ofthe anatomy the stent is implanted in after expansion of the stent insuch anatomy (such as lumen or mock vessel) or after formation ofdiscontinuities, or the stent of the present invention is configured tohave a composite compliance of at least ⅓^(rd) of that of the radialstrain (compliance) of the anatomy the stent is implanted in afterexpansion of the stent in such anatomy (such as lumen or mock vessel) orafter formation of discontinuities, or the expanded stent may have acomposite compliance of at least 50% of the radial strain (compliance)of the anatomy the stent is implanted in, or a composite compliance ofat least 65% of the radial strain (compliance) of the anatomy the stentis implanted in, under physiologic conditions. In a preferred example,the stent of the present invention is configured to have a compositecompliance after expansion in a body lumen (or a mock tube), or afterformation of discontinuities, ranging from 0.7% to 4%, or ranging from0.9% to 4%, or ranging from 1% to 4%, or ranging from 1.1% to 4%, orranging from 1.2% to 4%, or ranging from 1.5% to 4%, or ranging from 2%to 4%, wherein the lumen (or mock tube) has a compliance of about 5%,under physiological conditions. In another preferred examples, the stentof the present invention is configured to have an initial compositecompliance after expansion in a body lumen (or mock tube), ranging from0.1% to 0.5%, and has a second composite compliance after the initialcompliance, or after formation of discontinuities, ranging from 0.7% to4%, or the stent is configured to have an initial composite complianceafter expansion in a body lumen (or mock tube), ranging from 0.1% to0.7%, and has a second composite compliance after the initialcompliance, or after formation of discontinuities, ranging from 1% to4%, or the stent is configured to have an initial composite complianceafter expansion in a body lumen (or mock tube), ranging from 0.1% to 1%,and has a second composite compliance after the initial compliance, orafter formation of discontinuities, ranging from 1.2% to 4%, or rangingfrom 1.5% to 4%, or ranging from 2% to 4%, and wherein the lumen (ormock tube) compliance is about 5%. In another preferred example, thestent of the present invention is configured to have an initialcomposite compliance magnitude after expansion in a body lumen (or mocktube) where the lumen diameter ranges from 2.5 mm to 3.5 mm and thelumen (or mock tube) has a compliance of about 5%, and wherein theinitial stent composite compliance magnitude after expansion ranges from0.01 mm to 0.05 mm, or ranges from 0.01 mm to 0.06 mm, or ranges from0.01 mm to 0.07 mm, and where the stent has a second compositecompliance magnitude after the initial compliance, or after formation ofdiscontinuities, ranging from 0.07 mm to 0.15 mm, or ranging from 0.08to 0.15 mm, or ranging from 0.1 mm to 0.15 mm, under physiologicconditions. Scaffolds in accordance with this invention are configuredto circumferentially uncage allowing the stent and the lumen to have %radial compliance as described above. Scaffolds may also be formed tohave differing regions of radial compliance (radial strain) along theirlengths. For example, as shown in FIG. 16G-10, a scaffold 1070 includesa plurality of rings formed from struts 1074 and crowns 1076, as withpreviously described examples. Adjacent rings are joined by axiallylinks 178, and separation regions 1072 are formed in each of the rings.In a first end region (or segment) 1080 of the scaffold 1070, each ofthe rings have three separation regions 1072, making that region highlycompliant after expansion, and formation of discontinuities. In a secondor middle region (or segment) 1082, each ring includes only a singleseparation region, making that region less compliant than the firstregion 1083, and a third region (or segment) 1084 where each ring has apair of separation regions 1072, making the compliance of the thirdregion somewhere in between that of the first region 1080 and that ofthe second region 1082 (assuming that all other characteristics of thecircumferential rings are similar) The % radial strain (compliance) canbe measured utilizing for example the test apparatus in FIG. 35 which isadjustable for selecting the physiologic condition % radial strain(compliance) or displacement approximation and measuring radial strain(composite compliance) of implants, stents, or stent segments underphysiologic conditions. It is desirable to have substantially allsegments of the stent uncage by uncaging substantially all rings. Thestent may have a substantially similar radial strain (compliance) alongthe entire stent ring segments or can have a variable radial strain(compliance) among various ring segments or regions of the stent. Radialstrain (compliance) may be increased or decreased by configuring forexample one or more of the following: The number of separation regionsper ring, the type of stent design or pattern, the location of theseparation regions on each ring, the length, width, and/or thickness ofthe structural element where the separation region is located on thering, the pattern of the separation regions along the stent length orsegment, to name a few. The magnitude of displacement (expansion and/orcontraction) in the expanded stent configuration, in physiologicalenvironment, of the stent of this invention, in one example, having thedesired % radial compliance, ranges from 0.1 mm to 1 mm, preferablyranges from 0.15 mm to 0.5 mm, more preferably ranges from 0.2 mm to 0.5mm. The displacement (contraction and/or expansion) magnitude and rateare typically coupled (or synchronized with or corresponding to) withthe beating of the heart, the pressure or mean pressure adjacent to thestented segment, and/or contractility of the heart muscle, or otherphysiologic conditions. It is desirable to have a stent having highinitial strength sufficient to support a body lumen in the expandedstent configuration, and at the same time said stent is configured tohave one or more % radial strain (compliance) values or ranges along thelength (or segments or regions) of the stent rings. Shape memory stentstend to have weaker strength (or crush force) due to the properties andprocessing of the material. Stent formed from shape memory alloy tend tohave closed cell designs to compensate for such weakness in strength.However, it is desirable to have stents formed from shape memory alloyshaving strength in the expanded configuration and having separationregion on at least some rings to uncaging the rings (forming one or morediscontinuities in the circumferential ring path sufficient to uncagesaid rings). The stent formed from shape memory alloy can thus beconfigured to have high crush resistance in the expanded configurationand the desired displacement or radial strain (compliance) along varioussegments of the stent rings as described above to accommodate the radialstrain (compliance) of the anatomy where the stent is implanted in, orthe stent is configured to have the desired radial strain (orcompliance). In some cases, it is desirable to have a stent having highcrush strength in the expanded configuration, and have radial strain(compliance) or radial displacement magnitude (larger or smaller) byforming separation regions or breaking sections along thecircumferential path of the stent rings, uncaging the stent or one ormore stent segments and achieving the desired level or range ofdisplacement or radial strain (compliance) for the stent ring or stentsegment. In other or same cases, it is desirable to have a stent havinghigh crush strength in the expanded configuration, and have radialstrain or radial displacement magnitude (larger or smaller) and/or havecontraction magnitude being different from expansion magnitude, byforming separation regions or breaking sections along thecircumferential path of the stent rings uncaging the stent or stentsegment and achieving the desired level or range of displacement orradial strain for the stent rings or stent segment. In addition to otherstent design configurations such as supporting features described inFIGS. 23C and 23D can be utilized to achieve the desired radial strain,expansion magnitude, and/or contraction magnitude. In some cases thestent of this invention can be configured to have high crush resistancein some segments of the stent in the expanded configuration and havingsubstantially low % radial strain in such segments, while achievingcertain desired radial strain value or displacement magnitude in othersegments of the stent (while having similar crush resistance or lowercrush resistance to the other segments of the stent). This can bespecially suited for heart valves stents where certain segments requireanchoring of the stent and therefore require high crush resistance,while other segments of the stent require higher % radial strain(compliance) or contractility magnitude usually in stent ring segmentsadjacent to or the segment containing the stent valve. Stents formedwith separation regions configured to uncage in the circumferential ringpath can have an advantage by accommodating the contractility of theannulus or lumen where it is necessary and have strength and low radialstrain (compliance) in areas or segments where it is not necessary, orwhere it is important to anchor or affix the implant structure.

Referring now to FIG. 16G-11. A scaffold 1086 comprising a plurality ofcircumferential rings 1090 is formed from struts 1092 and crowns 1094,generally is described above. Each of the circumferential rings 1090includes a pair of separation regions 1088, and adjacent circumferentialrings 1090 are joined by axial links 1096. Scaffold 1086 differs fromthose described previously in at least that it includes a plurality ofreinforcement elements or features 1098 attached to adjacent struts 1092near locations where they are joined into crowns 1094 or crown region orstrut region. The struts and crowns of the scaffold 1086 will be formedfrom any of the non-degradable materials described (or degradablematerial having high crush resistance) and will typically be of thestent type intended for balloon expansion, but can also be used forshape memory stent type. That is, the primary material of the scaffold1086 will be formed from a malleable, non-elastic metal or othermaterial in one example. In contrast, the reinforcement features 1098will be typically formed from a resilient or elastic material, usually ashape-memory metal alloy, a spring stainless steel, or the like. Asillustrated, the reinforcement features 1098 will act as a spring tohelp open the stent from its crimped configuration (not illustrated) toits open configuration (as shown in FIG. 16G-11). When the scaffold 1086is crimped, the spring-like reinforcement features 1098 will be closedto compress the spring and impart a spring force which helps to open thescaffold during balloon or other expansion. As illustrated, thespring-like reinforcement features 1098 can be located adjacent theseparation regions 1088. In this way, the opening force provided by thereinforcement features will offset at least some of the tension impartedto the separation features by balloon expansion. Additionally, thespring-like retention features will enhance the resilience of the openscaffold increasing its compliance within the blood vessel or other bodylumen. The reinforcement elements can also help further expand the stentto a second larger configuration after inward recoil from first expandedconfiguration. The stent in this example have separation regions formingdiscontinuities after expansion of the stent to the deployedconfiguration uncaging the stent along the stented segment.

Referring now to FIG. 16H-1 through 16H-5, an additional type ofseparation region 160 is illustrated. The separation region 160 isformed between a first hollow strut segment 162 and a second hollowstrut segment 164. A core 166 has one end received in a central passage168 of the first hollow strut segment 162 and a second end received in acentral passage 170 of the second hollow strut segment 164. The strutsegments 162 and 164 will usually be non-degradable, typically being ametal as described elsewhere herein, while the core 166 may be eitherdegradable or non-degradable. In cases where the core 166 isnon-degradable, the separation region 160 will typically be initiallystabilized with an adhesive and/or a sleeve or other encapsulationduring deployment and expansion. After implantation, the biodegradableadhesive and/or encapsulation will degrade, eventually allowing eitheror both of the hollow strut segments 162 and 164 to axially sliderelative to the core 166, thus forming an expansion joint, and/orallowing the stent to further expand.

Alternatively, where the core 166 may be itself biodegradable, in whichcase the core may be either attached to one or both of the hollow strutsegments 62 and 64 or may be free to axially translate relative toeither or both of the hollow strut segments 62 and 64. When the core 166is biodegradable, the biodegradation of the core after implantation willbe relied on primarily in one example to achieve separation of thesegments 162 and 164.

As a further alternative, a biodegradable core 166 may be joined withineither or both of the hollow strut segments 162 and 164 using abiodegradable adhesive. Such designs may provide a further failsafemechanism for biodegradation and release of the strut segments.Alternatively, the use of multiple biodegradation patterns in the coreand surrounding adhesives may allow a sequential biodegradation of thedifferent elements to achieve different levels of expansion andseparation between the strut segments.

As shown in FIG. 16H-2, for deployment and expansion, the hollow strutsegments 162 and 164 will initially be joined in an abutting fashionwith the core 166 serving as a link or stabilizing bar or element. Thecore 166 may be joined to the hollow struts 162 and 164 by abiodegradable or a non-biodegradable adhesive, depending in part onwhether or not the core 166 itself is biodegradable. Alternatively, oradditionally, the struts 162 and 164 may be joined by a biodegradableexternal sleeve 172, as shown in FIG. 16H-3.

As further shown in FIG. 16H-4, a core 174 may include a necked region176. By properly selecting the size or cross-sectional area of thenecked region 176, the biodegradation time for a core formed from aparticular biodegradable material may be programmed into the core 174.

Still further alternatively, a core 178 may itself be separated intocore segments 180 and 182 joined by a pin 184 received in a hole orpassage 186, as shown in FIG. 16H-5. The pin 184 may be formed as partof the core segment 180 itself or may be a separate element or componentwhich freely slides in both the hole 186 and a second hole (not shown)in the first core segment 180.

A separation region with the core design of FIGS. 16H-1 to 16H-3 willusually not totally separate, and some portion of the core 166 willremain in the passage 170 even after a vessel has completedpost-implantation remodeling and expansion. This is advantageous as thedesign does not leave voids in the scaffold structure which supports thetissue. Such designs will however limit separation of the adjacent strutsegments in the radial direction which can limit the expansion of thestent as a whole and reduce expansion in response to vessel remodeling.Provision of a degradable region 176 (FIG. 16H-4) or a pin 184 and ahole 186 (FIG. 16H-5) in the core can allow complete separation undersome circumstance which can enhance the complete mobility of the stentto enhance the response to vessel remodeling.

Still further separation regions are illustrated in FIGS. 16I-1 through16I-4. A butt joint 200 connecting strut segments 202 and 204 hasenlarged interface elements 206 and 208 at the terminal end of eachstrut segment as illustrated in FIG. 16I-1. Opposed surfaces on therespective interface elements are joined with an adhesive, cement,polymer, or any of the other degradable immobilizing materials 9described herein. Alternatively, the terminal ends may be joined by anyof the sleeve-like immobilizing element's described elsewhere herein. Ahook joint 210 connecting strut segments 212 and 214 has hook-likeinterface elements 216 and 218 at the terminal end of each strut segmentas illustrated in FIG. 16I-2. Opposed hook surfaces on the respectiveinterface elements may be clasped together to enhance tensile strengthof the resulting joint (and hoop strength of the scaffold ring), and maybe further immobilized with an adhesive, cement, polymer, or any of theother degradable immobilizing materials described herein. Asillustrated, the terminal ends are joined by a sleeve-like immobilizingelement 219 which may be formed as described elsewhere herein. FIG.16I-3 illustrates a joint 220 which is a variation of the butt joint ofFIG. 16I-1 Joint 220 has connecting strut segments 222 and 224 withenlarged interface elements 226 and 228 having nesting, curved surfacesat the terminal end of each strut segment. The curved surfaces have ageometry similar to a nerve synapse and allow some bending flexibilityin the separation region before and after the immobilizing element (notshown) degrades. The flexibility improves contact if the strut segmentsbecome misaligned which can enhance crush resistance of the stent orother prosthesis. Joint 230 has connecting strut segments 232 and 234with enlarged interface elements 236 and 238 having flat surfaces at theterminal end of each strut segment which are angled or inclined relativeto the common axis of the strut segment. The inclined surface can sliderelative to each other as the circumferential ring expands or contractswhich can improve compliance of the stent or other prosthesis. Theinterface elements 236 and 238 can be temporarily immobilized by any ofthe adhesives, cements, polymers, sleeves, or other immobilizingcomponents described elsewhere herein.

Adhesion and immobilization of the terminal ends of adjacent strutsegments (can also apply to crown regions) can also be enhanced bycreating surface features on those ends. As illustrated for example inFIGS. 16I-5, a portion of a scaffold 400 has short lock-and-keyseparation regions 402 formed in circumferential rings 404 having struts406 joined by crowns 408. The terminal ends of at least some of theadjacent strut segments joined by the separation regions 402 have holes,pores, perforations, bumps, or other surface features that provideattachment points for degradable sleeves 412 or other immobilizingelements that circumscribe the separation regions while the scaffold 400is being deployed. While illustrated on short lock-and-key separationregions 402, the use of such anchoring surface features will find usewith long lock-and-key separation regions as well as all types ofseparation regions which are immobilized by sleeves or othercircumscribing immobilizing elements.

As a further embodiment or example, immobilization of the terminal endsof adjacent strut segments on lock-and-key separations regions can beenhanced by creating features on the interfacing surfaces of the“tongue” and “slot” of the lock and key. For example, as illustrated inFIG. 16I-6, a portion of a scaffold 500 has long lock-and-key separationregions 502 formed in circumferential rings 504 having struts 506 joinedby crowns 508. Opposed surfaces of the tongue 510 and the slot 512 haveundulating or “wavy” topographies which increase the surface areavailable for bonding with adhesives, cements, polymers, glues, or thelike. In addition to increasing the available surface area for bonding,these surface features can physically interlock to further prevent axialseparation of the strut segments. In addition to undulations, asillustrated, suitable interface features include serrations, saw-toothpatterns, chevron patterns, ramps, and the like. Such interlock featurescan be used with all lock-and-key and other separation region designsthat have suitably oriented opposed surfaces and that allow radialseparation or movement after the initial immobilization has degraded.

In still further examples of the uncaging stents of the presentinvention, scaffolds 1100 may be fabricated or modified to haveopenings, gaps, or breaks within the structures of individualcircumferential rings and forming or placing bridging elements to bridgethe openings, breaks, or gaps, as illustrated in FIG. 16I-7. Scaffold1100 comprises of plurality of adjacent circumferential rings 1102 eachof which comprises struts 1104 and crowns 1106, arranged generally asdescribed previously herein. Adjacent circumferential rings 1102 arejoined by axially links 1108, and openings or breaks may be formed ineither the struts as shown at 1110 and/or in the crowns as shown at 1112and where a bridging elements are formed to bridge said openings orbreaks. Exemplary openings and breaks are typically in the form of gaps,as will be described in more detail below. The bridging elements can beformed from degradable material such as degradable polymeric material ordegradable metallic material, wherein the degradable materialencapsulates the strut or crown region, or is inserted inside (orwithin) the non-degradable material strut or crown regions ends, orjoined as a butt joint with the non-degradable stent material at theends (or junction) or opening junctions, or other methods of attachmentsuch as FIGS. 16I-A-C. The degradable material degrades from one monthto 3 years, preferably degrades from 2 months to 2 years, morepreferably degrades from 2 months to 18 months. The stent in thisexample will have at least one bridging element per ring (two bridgingelements per ring are shown in the figure) to sufficiently uncage thesaid ring. The length and number of bridging elements per ring candetermine the magnitude of further expansion and/or displacementmagnitude the stent is cable of performing after uncaging. Theadvantages of such stent configuration is having a stent that uncagesafter expansion from a crimped configuration to an expanded largerconfiguration, having high crush resistance in the expandedconfiguration, yet being able to uncage after expansion, and/or afterdegradation of at least one bridging element per ring. FIGS. 16I-16A,16I-16B, and 16I-16C illustrate other examples of bridging elements.Bridging elements for example can bridge all or part of the crown orcrown region, and/or all or part of a strut or strut region. Bridgingelements in one example can have sizes, shapes, and dimension similar ordifferent to structural elements being bridged. In other examples,bridging elements sizes, shapes, and dimensions are similar toreinforcement elements description described in more detail in othersections of this application. Another example, bridging elements havethe shape of a strut or strut region, crown or crown region, or othershapes.

Referring now to FIGS. 16I-8A and 8B, separation regions 1118 in theform of gaps may be configured to contact, touch, or meet when thescaffold is in its crimped configuration, as shown in FIG. 16I-8A. Theseinitially closed gaps 1118 will then open to leave a space, or gaptherebetween when the scaffold 1116 is radially expanded or after thescaffold is expanded, as shown in FIG. 16I-8B. Typically, prior toexpansion of the scaffold 1116, the gaps 1118 will be free fromadhesives, sleeves, or other temporary restraining features which havebeen employed in other examples of the present invention. Thearrangement of the “closed” gaps 1118 is selected so that the “open”gaps 1120 form as the scaffold 1118 is expanded or after scaffoldexpansion by a balloon or otherwise, so that the expanded scaffold 1116will have sufficient hoop strength (or crush resistant force) tomaintain patency of the blood vessel or other body lumen while allowingan enhanced level of compliance (radial strain) to reduce or eliminatecaging of the body lumen, typically a blood vessel, or heart valve,after implantation. The stent having said gaps allow for vaso-dilatationin the stented segment, and/or further expansion after deployment. Inanother example, the free ends (where the gap is) is coated with anadhesive or a polymer, or other means to hold the gaps in the “closed”position upon expansion of the scaffold from a crimped configuration toa deployed configuration. This allows the structural elements where thegaps are located to have improved vessel (or lumen) support in the gapregion, improved uniformity of expansion in the gap region, and improveddrug delivery to the tissue adjacent to the gap to suppress neointimalproliferation for example. The gaps can open up when the scaffold is inthe expanded configuration immediately, or over time after expansion,uncaging the vessel or lumen. Various adhesives, polymers, and othertemporary holding means are described throughout the application. Asshown in FIGS. 16I-8A & B, the gaps pattern is such that the gap onadjacent rings are rotationally offset. This allows for improved stentstrength or crush resistance in the expanded scaffold configuration byreducing the impact of having a discontinuity in each ring, reducefish-scaling along any axial path (or line) of the scaffold length,reduce having uncovered vessel or lumen area (or large uncovered area),lower recoil of the scaffold after expansion. The gap can be formed onstructural element such as a strut, where the strut is adjacent to axiallinks (as shown in FIGS. 16I-8A & B), or can also be formed on a strutadjacent to two different axial links, each axial link connecting thering where the gap is to an adjacent ring (not shown). Gaps can also beformed on struts or other structural elements not adjacent to axiallinks. As discussed in other examples, the number of gaps from one ringto another can vary. In one example, it might be desired for abifurcation stent for instance to have several gaps in one or more ringsin a mid-segment of the stent, and a lesser number of gaps in rings inother segments of the stent. In one preferred example, having one ormore gaps on at least some rings where gaps on adjacent rings arerotationally offset, and having one or more axial links connecting atthe at least some rings where at least some of the links connectingadjacent rings are rotationally offset. In one preferred example, havingone or more gaps on at least some rings where gaps on adjacent rings arerotationally offset, and having one or more axial links connecting theat least some rings where the links connecting adjacent rings arerotationally offset. In one example, having one or more gaps on at leastsome rings where no more than two gaps on adjacent rings are axiallyaligned, and having one or more axial links connecting the at least somerings where the links connecting adjacent rings are rotationally offset.In one example, having one or more gaps on at least some rings where nomore than three gaps on adjacent rings are axially aligned, and havingone or more axial links connecting the at least some rings where the oneor more links connecting some adjacent rings are rotationally offset. Inone example, having one or more gaps on at least some rings where nomore than three gaps on adjacent rings are axially aligned, and havingat least two links connecting adjacent rings. In one example, having oneor more gaps on at least some rings where no more than three gaps onadjacent rings are axially aligned, and having at least three linksconnecting adjacent rings. Gaps are also applicable to other stentdesign types such as closed cell designs, self-expanding, etc. and othertypes as discussed throughout this application. The free ends of thegaps can have a variety of shapes and dimensions, for example to beatraumatic ends, to have more strength, to improve coverage, to havemore surface area, to name a few. In one example, there is no more thanone gap for at least some rings, in other examples, there are two ormore gaps for at least some rings, where the gaps on adjacent rings arerotationally offset. The free ends in FIGS. 16I-8A show the two freeends in contact at the free end, but they can also be in contact atregions adjacent to the free end.

Other examples of gaps structures which are initially closed and openupon expansion or after expansion of the scaffold are illustrated inFIGS. 16I-9 and 10. In FIG. 16I-9, each gap 1124 comprises a pair ofshort, serpentine segments having tips which engage each other along anaxial line when the scaffold is closed. As shown in FIG. 16I-10, eachgap structure 1126 comprises a short serpentine segment where the endsof the segment lie generally parallel to each other (but can have otherconfigurations) when the scaffold is in its crimped configuration. Thegap structure 1124 shows the ends touching, while the gap structure 1126shows the end space slightly apart.

Referring now to FIGS. 16I-11A and 11B, a scaffold 1128 comprisescircumferential rings as described previously. Gap regions 1130 areformed in the circumferential rings of the scaffold, with the gaps beinginitially open when the stent in its crimped or unexpandedconfiguration, as shown in FIG. 16I-11A. The gap regions open further asshown at 1132 in FIG. 16I-11B when the stent it in its radially expandedconfiguration. The stent with such allow for vaso-dilatation in thestented segment, and/or further expansion after deployment. In anotherexample, the free ends (where the gap is) are connected with a suture orother temporary means to hold the struts together upon expansion of thescaffold from a crimped configuration to a deployed configuration. Thisallows the structural elements where the gaps are located to haveimproved vessel (or lumen) support in the gap region, improveduniformity of expansion in the gap region, and improved drug delivery tothe tissue adjacent to the gap to suppress neointimal proliferation forexample. The gaps can open up further when the scaffold is in theexpanded configuration immediately, or over time after expansion,uncaging the vessel or lumen. As shown in FIGS. 16I-11A & B, the gapspattern is such that the gap on adjacent rings are rotationally offset.This allows for improved stent strength or crush resistance in theexpanded scaffold configuration by reducing the impact of having adiscontinuity in each ring, reduce fish-scaling along any axial path (orline) of the scaffold length, reduce having uncovered vessel or lumenarea (or large uncovered area), lower recoil of the scaffold afterexpansion. The gap can be formed on structural element such as a strut,where the strut is adjacent to axial links (as shown in FIGS. 16I-8A &B), or can also be formed on a strut adjacent to two different axiallinks, each axial link connecting the ring where the gap is to anadjacent ring (not shown). Gaps can also be formed on struts or otherstructural elements not adjacent to axial links. As discussed in otherexamples, the number of gaps from one ring to another can vary. In oneexample, it might be desired for a bifurcation stent for instance tohave several gaps in one or more rings in a mid-segment of the stent,and a lesser number of gaps in rings in other segments of the stent. Inone preferred example, having one or more gaps on at least some ringswhere gaps on adjacent rings are rotationally offset, and having one ormore axial links connecting at the at least some rings where at leastsome of the links connecting adjacent rings are rotationally offset. Inone preferred example, having one or more gaps on at least some ringswhere gaps on adjacent rings are rotationally offset, and having one ormore axial links connecting at the at least some rings where the linksconnecting adjacent rings are rotationally offset. In one example,having one or more gaps on at least some rings where no more than twogaps on adjacent rings are axially aligned, and having one or more axiallinks connecting the at least some rings where the links connectingadjacent rings are rotationally offset. In one example, having one ormore gaps on at least some rings where no more than three gaps onadjacent rings are axially aligned, and having one or more axial linksconnecting the at least some rings where the one or more linksconnecting some adjacent rings are rotationally offset. In one example,having one or more gaps on at least some rings where no more than threegaps on adjacent rings are axially aligned, and having at least twolinks connecting adjacent rings. In one example, having one or more gapson at least some rings where no more than three gaps on adjacent ringsare axially aligned, and having at least three links connecting adjacentrings. Gaps are also applicable to other stent design types such asclosed cell designs, self-expanding, etc. and other types as discussedthroughout this application. The free ends of the gaps can have avariety of shapes and dimensions, for example to be atraumatic ends, tohave more strength, to improve coverage, to have more surface area, toname a few. In one example, there is no more than one gap for at leastsome rings, in other examples, there are two or more gaps for at leastsome rings, where the gaps on adjacent rings are rotationally offset.

Gaps may also be formed with overlapping structures, as shown in FIGS.16I-12A and 12B. Scaffold 1126 comprises separation regions 1138 wherethe free or open ends of the struts which have been formed as such orformed and detached from each other are shown to overlap so that theymay slide adjacent to each other as the scaffold 1136 iscircumferentially opened or after.

A variety of different overlapping gap structures are illustrated inFIGS. 16I-13A through 13F. A separation region 1140 comprising curvedstruts with overlapping ball termini is illustrated in FIG. 16I-13A. Aseparation region 1142 comprising parallel struts having tapered ends isshown in FIG. 16I-13B. A separation region 1144 comprising struts havingopposed ratcheting surfaces is shown in FIG. 16I-13C. A separationregion 1146 comprising simple curved struts which loosely interlock isshown in FIG. 16I-13D. A separation region 1148 comprising hooked orcurved ends on strut segments which interlock is shown in FIG. 16I-3E.The interlocking ends of separation region 1148 will generally permitseparation preferably in a radial direction and not in an axiallydirection as described previously with respect to other embodiments ofthe separation regions, but can in some cases separate in both. Aseparation region 1150 with filler struts increasing the coverage andthe resulting gap is shown in FIG. 16I-13F.

Referring now to FIGS. 16I-14A and 14B, a separation region 1154comprising overlapping, offset strut segments can be left free to allowthe segments to slide relative to each other as the scaffold isexpanded, as shown in FIG. 16I-14A. Alternatively, a sleeve 1156 may beformed over the parallel strut segments, as shown in FIG. 16K-14B.Alternatively, an adhesive material can hold the segments togetherduring expansion (or deployment) from a crimped configuration to anexpanded larger configuration. The material is usually temporarydegrading over a period ranging from expansion of the stent to afterexpansion of the stent, typically in a time period ranging from 30 daysto 6 months.

While the gap structures of the present invention have been illustratedprimarily in the strut regions of the scaffold, they may also be formedin the crown regions. For example, as shown in FIG. 16I-15A, aseparation region 1160 may comprise a pair of nested, J-shaped strutends which together form a crown having a gap therein. Such a nestedstructure will help keep the struts together as the scaffold is beingradially expanded but will allow the struts (crowns) to at leastpartially separate (or completely separate) in order to enhancecompliance of the scaffold after expansion. Optionally, as shown in FIG.16I-15B, a sleeve 1162 may be placed over the nested crown 1160 in orderto enhance the strength of the crown regions as the scaffold is expandedor to enhance strength after expansion. The sleeve will typically bebiodegradable so that the separation region allows the strut ends tomove relative to each other after the sleeve degrades.

Referring now to FIGS. 16I-16A through 16C, scaffolds 1170 may be formedwith separation regions in the form of biodegradable bridge elements1172 within the crowns of a circumferential ring. In particular, asshown in FIG. 16I-16B, a biodegradable bridge region 1174 may be securedto attachment structures 1176 on adjacent structures of a crown (oralthough not illustrated, a strut). The bridge element 1174 thus forms abiodegradable crown 1172 in the circumferential ring 1102 of thescaffold 1170. The “crown” bridge 1172 will thus be present as thescaffold is radially expanded and will provide hoop strength and crushresistance in the period following implantation. The degradable bridge1172 will, however, lessen in strength over time and eventually fullydegrade, enhancing the compliance of the scaffold 1170 in order to“uncage” the scaffold after implantation. FIG. 16I-16C is an image ofthe scaffold 1170 which has been fabricated by the methods of thepresent invention. The bridging elements as describes previously cancontain the ends of the patterned stent structure or be contained withinor attached as a butt joint. FIG. 16I-16A is another example ofattaching bridging elements to the usually non-degradable frame,providing discontinuities when the degradable bridging element degrade,uncaging the ring and the stent.

Referring now to FIG. 17, serpentine rings 80 and 82 may be formed witha bifurcated joint 84 having an upper element 86 joined to one end ofthe rings and a lower element 86 b attached to the other end of therings. The joint is held together by degradable constricting elements88, which may be sleeves, coils, rivets, or any of the other elementsdescribed herein which erode or fatigue over time in response to theendoluminal environment and/or the application of external energy.

As shown in FIG. 18, the butt joints described above may include a pinreceived on one segment 90 a of a strut 90 which is received in areceptacle 94 received in the other segment 90 b of the strut. The pinshelp maintain structural integrity of the joint prior to breaking of theadhesive or other element holding the ends together.

Referring now to FIG. 19, as alternatives to adhesives and otherbiodegradable elements which can hold pre-formed separated segments ofthe circumferential scaffold together, the present invention may useMagnets. For example, in a bifurcated joint 102 similar to thatillustrated in FIG. 17, a magnet 102 having a north pole 102 a on anupper element 100 and a south pole of the magnet 102 b on the lowersegment of the joint. The magnets may comprise high flex magnets of thetype which can resist substantial forces, including the forces ofexpanding the circumferential scaffold. The magnets, however, can bereleased by application of a greater external magnetic field, forexample, from an MRI unit, to release the segments and open the rings ofthe circumferential scaffold.

FIG. 20 illustrates a different key and lock junction 106 in the strut104 which has less stress area and therefore allows the stent scaffoldto expand while maintaining its structural integrity to providestrength.

The circumferential scaffolds of the present invention may be formedfrom tubular elements, such as strut 110, and the tubular elements mayinclude pins 112 which can be received in the lumens or receptacles 114of an adjacent strut segment. This facilitates having a structuralintegrity for the stent to have sufficient strength upon expansion.

One skilled in the art can appreciate that the location, number, anddistribution of said breakage sections is configured to allow the stentprosthesis to be deployed to a larger configuration, to have astructural integrity in the expanded configuration, and to sufficientstrength to support a body lumen. This includes breakage sections (orseparation regions) on at least some rings, and/or hinges, and/orstruts.

III. Non-Degradable Prosthesis (or Degradable with High CrushResistance) Having Rings with Constrained Hinges

Referring now to FIG. 22, adjacent struts 40 of a serpentine ring 14 maybe constrained by a sleeve 118 or similar biodegradable constraint. Thebiodegradable constraint will hold the adjacent strut segments togetherduring expansion of the circumferential scaffold. After implantation,the sleeve 118 or other constraint will erode or degrade over time, andthe struts 42 will be freed to expand, thus uncaging or un-jailing theprosthesis. In another example, an adhesive joining the two adjacentelements holding them together after deployment of the stent, then theadhesive degrades freeing the two adjacent element to further expand,uncaging the vessel.

In a variation of the constrained hinge of FIG. 22, a separation region1200 may be formed between adjacent struts 1202 of the serpentine ringof a scaffold, as shown in FIG. 22A. The adjacent struts 1202 aregenerally joined by a conventional crown 1204, as illustrated. Atcertain locations in the ring, however, the adjacent struts may becollapsed and split apart as shown at 1206. The split allows theserpentine ring to open to form a gap, as described with priorembodiments, as the scaffold is expanded. Optionally, the splitstructure 1206 may be covered with a biodegradable sleeve 1208, as shownin FIG. 22B. With the sleeve in place, the split strut 1206 will notseparate until after the sleeve has degraded. Alternatively, an adhesivematerial is used to join the adjacent 1206 struts to hold the segmentstogether upon expansion of the stent or in the expanded stentconfiguration. The adhesive degrades over time freeing the segments anduncaging the ring as a result of creating or forming one or morediscontinuities along the path of the circumferential ring.

IV. Non-Degradable Prosthesis (or Degradable Having High CrushResistance) Having Rings with Active Joints

Referring now to FIGS. 23A and 23B, an active hinge 122 may be formedwhich joins struts 124 on a pivot pin 126. The pivot 126 is patterned inone end of a lower port strut segment and received in a slot 128 in theupper strut segment. The slot is asymmetric and has a face 130 which isangled relative to a lower face 132 formed adjacent the pivot pin 126.After the circumferential scaffold including such active joints isexpanded, the joint will be compressed by the body lumen so that it canassumes the configuration of FIG. 23A. Over time, however, as luminalremodeling expands the luminal diameter, the joint will be able to open,as illustrated in FIG. 23B, thus lessening any jailing or caging as aresult of the prosthesis. In one example, the active hinge is coatedwith a polymeric material, or with an adhesive material to hold theactive hinge in place upon deployment. The active hinge material canalso or instead be placed in the straight section of the ring on astrut.

Referring now to FIGS. 23C and 23D, active hinges with supportingfeatures having separation regions are described. Active hinges withsupporting features are described in US2008/0177373 (U.S. applicationSer. No. 12/016,077) commonly assigned with the present application, thefull disclosure of which is incorporated herein by reference.

A portion of a first serpentine ring 300 (FIG. 23C) and a secondserpentine ring 302 (FIG. 23D) is joined by axial links 314 to adjacentserpentine rings (not shown). Each serpentine ring 300 comprises pairsof axial struts 316 joined by a hinge-like crown 318 at each end. Asupporting feature 320 is disposed between at least some of the adjacentaxial struts 316 and connected so that the feature will expandcircumferentially as the struts separate as the serpentine ring 300 isexpanded during deployment. The supporting features 20 are in agenerally closed U-shaped configuration prior to expansion, as shown inFIGS. 23C and 23D, and open into a shallow V-shape along with theopening of the axial struts 316 about the crowns 318 during radialexpansion of the serpentine rings 300. Supporting features can take avariety of shapes, contact points, locations, etc., as described in theapplication above. Supporting features 320 enhance the crush resistanceof the stent after radial expansion, help resist recoil, and provideadditional area for supporting the vascular or other luminal wall andoptionally for delivering drugs into the luminal wall.

While the supporting features enhance the crush resistance, they alsoenhance the hoop strength which contributes to the undesirable cagingeffect discussed in detail elsewhere in this application. In order tocontrol the hoop strength, without significantly diminishing the crushresistance, separation regions can be formed in crowns of the supportingfeatures 320 (FIG. 23C) and/or the serpentine ring (FIG. 23D) or in thestruts. As shown in FIG. 23C, the crowns of some or all of thesupporting features may have separation regions 330. As illustrated, theseparation regions 330 comprise a break or discontinuity in the crownwhich is immobilized by a degradable sleeve as an example formed overthe opposed surfaces of the adjacent crown segments, but theseseparation regions could have any of the structures described elsewhereherein for separation within the vascular or other physiologicenvironment. As shown in FIG. 23D, separation regions 332 are in some orall of the crowns 316 of serpentine ring 300 (they can also be instruts). As illustrated, the separation regions 332 comprise a break ordiscontinuity in the crown which is immobilized by an adhesive, cement,or polymer between the opposed surfaces of the adjacent crown segmentsor on the surfaces, but these separation regions could have any of thestructures described elsewhere herein for separation within the vascularor other physiologic environment. In other examples, the separationregions can also or instead be formed on the struts of the supportingfeatures 320.

As described, the separation regions of present invention have beenemployed to enhance compliance (radial strain) of a stent or otherluminal prostheses after implantation in a blood vessel or other bodylumen such as the annulus of a valve. As shown in FIGS. 23E-1 through23E-3, however, the separation regions can provide other utilities. Forexample, a scaffold in 1220 comprising circumferential rings 1222including struts 1224 and crowns 1226 may be modified with separationregions to enhance opening for access to bifurcations in blood vessels.While the majority of circumferential rings 1222 in scaffold 1220 arejoined by non-separating axial links 1128, in at least one locationwithin the stent, adjacent circumferential rings 1222 may be joined byaxial links 1230 comprising separation regions. Usually, thecircumferential rings on each side of the separating axial links 1230will also have separation regions 1232 present in at least somelocations. In this way, as shown in FIG. 23E-3, after the scaffold 1120is placed in a main vessel (MV) adjacent to a branch vessel (BV),expansion of a balloon 1240 within the scaffold 1120 will causepreferential opening 1238 over a middle section of the stent which isaligned with the branch vessel. Such preferential opening will occurbecause the balloon is able to separate the axial links 1230 which aretype which preferentially separates in the radial direction (aspreviously described herein). Additionally, the circumferential ringsimmediately adjacent to the opening 1238 will also be able to partiallyexpand into the opening by virtue of the separation regions 1232 inthose adjacent circumferential rings.

In some examples the shapes of the reinforcing elements can besubstantially round (solid round wire or hollow round wire),rectangular, square, egg shaped, or other shapes and geometries. Thesize of the reinforcing elements in one example are substantially thesame size/geometry as the hinges and/or struts they are couple to,and/or smaller size/geometry, and/or or larger size/geometry. In oneexample, the ends of the reinforcing elements are atraumatic, and/orsmooth, and/or have bulbous shape or rounded shape or larger crosssectional area compared to attached or adjacent structural element. Inone example the reinforcing elements surface finish is similar topolished vascular metallic stents. In another example, the surfacefinish is textured surface. In a preferred example, the stent prosthesisis a coronary stent prosthesis. In another example, the stent prosthesisis a vascular stent prosthesis. In another example the stent prosthesisis a non-vascular stent prosthesis.

V. Materials of Construction

Typically, In one example, the non-degradable materials will comprise,or formed from, metals and metal alloy, such as stainless steel, such as304V, 304L, and 316LV stainless steel; steel alloy such as mild steel;cobalt based alloy such as cobalt chrome; L605, Elgiloy, Phynox;platinum based alloy such as platinum chromium, platinum iridium, andplatinum rhodium; tin based alloys; rhodium; rhodium based alloy;palladium; palladium base alloy; aluminum based alloy; titanium or theiralloy; rhenium based alloy such 50:50 rhenium molybdenum; molybdenumbased alloy; tantalum; gold or their alloy; shape memory metal or alloy;chromium based alloy; nickel-titanium alloy such as linear-elasticand/or super-elastic nitinol; nickel alloy such asnickel-chromium-molybdenum alloys (e.g., INCONEL 625, Hastelloy C-22,Hatelloy C276, Monel 400, Nickelvac 400, and the like);nickel-cobalt-chromium-molybdenum alloy such as MP35-N;nickel-molybdenum alloy; platinum enriched stainless steel; combinationthereof; or the like, and other malleable metals, or plasticallydeformable when expanded from a crimped configuration to an expandedconfiguration, of a type commonly employed in stent and prosthesismanufacture. In other examples, however, the non-degradable material maycomprise a non-degradable polymer, such as polyaryletherketone;polyetheretherketone; polyimide, polyethylene such as UHMW, HDPE, LDPE,or others; polypropylene; polyester; polyethylene terephthalate;polycarbonate; polysulfone; polyphenylsulfone; polyethersulpone, Ultem;polyetherimide; polyurethane; polyamide; nylon such as nylon 12, nylon6, nylon 6-6, or others; polyvinylchloride; PTFE; FEP; ETFE; PFA; PVDF;polyvinylchloride; acrylobutadiene styrene; Delrin;polymethylmethacrylate; polystyrene; polyacrylamide, polyphenylsufide;PEBAX; or other materials. In still other examples, the non-degradablematerial may comprise an elastic metal, such as a shape or heat memoryalloy, shape memory polymer, or superelastic materials, typically anickel-titanium alloy; a spring stainless steel; Ni50-Mn28-Ga22;copper-aluminium-nickel; alloys of zinc, copper, gold and iron;iron-based alloy such as Fe—Mn—Si; copper-based alloy such as Cu—Zn—Aland Cu—Al—Ni; poly(ε-caprolactone)dimethacrylate; PVDF/PMMA; PVDF/PVA;PLA/PVAc; or other, or the like.

In an example of metal and metal alloy comprise, or composed from: asstainless steel, such as 304V, 304L, and 316LV stainless steel; steelalloy such as mild steel; cobalt based alloy such as cobalt chrome;L605, Elgiloy, Phynox; platinum based alloy such as platinum chromiumplatinum iridium, and platinum rhodium; tin based alloys; rhodium;rhodium based alloy; palladium; palladium base alloy; aluminum basedalloy; titanium or their alloy; rhenium based alloy such 50:50 rheniummolybdenum; molybdenum based alloy; tantalum; gold or their alloy;silver or their alloy; shape memory metal or alloy; chromium basedalloy; nickel-titanium alloy such as linear-elastic and/or super-elasticnitinol; nickel alloy such as nickel-chromium-molybdenum alloys (e.g.,INCONEL 625, Hastelloy C-22, Hatelloy C276, Monel 400, Nickelvac 400,and the like); nickel-cobalt-chromium-molybdenum alloy such as MP35-N;nickel-molybdenum alloy; tungsten or their alloy; platinum enrichedstainless steel; magnesium; magnesium alloy with less than 20% zinc oraluminum by weight, without or with one or more impurities of less than3% iron, silicone, manganese, cobalt, nickel, yttrium, scandium or otherrare earth metal; zinc or its alloy; bismuth or its alloy; indium or itsalloy, tin or its alloy such as tin-lead; silver or its alloy such assilver-tin alloy; cobalt-iron alloy; iron; iron containing alloys suchas 80-55-06 grade cast ductile iron, other cast ductile irons, AISI 1010steel, AISI 1015 steel, AISI 1430 steel, AISI 8620 steel, AISI 5140steel, or other steels; melt fusible alloys (such as 40% bismuth-60%tin, 58% bismuth-42% tin, bismuth-tin-indium alloys; alloys comprisingone or more of bismuth, indium, cobalt, tungsten, bismuth, silver,copper, iron, zinc, magnesium, zirconium, molybdenum, indium, tin; orother material; or the like.

In an example of polymeric material comprises, or composed from:polyaryletherketone; polyetheretherketone; polyimide, polyethylene suchas UHMW, HDPE, LDPE, or others; polypropylene; polyester; polyethyleneterephthalate; polycarbonate; polysulfone; polyphenylsulfone;polyethersulpone, Ultem; polyetherimide; polyurethane; polyamide; nylonsuch as nylon 12, nylon 6, nylon 6-6, or others; polyvinylchloride;PTFE; FEP; ETFE; PFA; PVDF; polyvinylchloride; acrylobutadiene styrene;Delrin; polymethylmethacrylate; polystyrene; polyacrylamide,polyphenylsufide; PEBAX; terpolymer, blends, mixes, or combinationthereof of lactides, caprolactones, trimethylene carbonate, and orglycolides such as polylactide, poly(L-lactide), poly-DL-Lactide,polylactide-co-glycolide (e.g., poly(L-lactide-co-glycolide) with 85%L-lactide to 15% glycolide), copolymer ofpoly(L-lactide-co-epsilon-caprolactone (e.g., weight ratio of fromaround 50 to around 95% L-lactide to about 50 to about 5% caprolactone;poly (L-lactide-co-trimethylene carbonate), polytrimethylene carbonate,poly(glycolide-trimethylene carbonate),poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids; protein such as elastin, fibrin, collagen,glycoproteins, gelatin, or pectin; poly-serine; polycaprolactam;cyclodextrins; polysaccharides such as chitosan, and hyaluronan;alginate; polyketals; fatty acid-based polyanhydrides, amino acid-basedpolyanhydrides; poly(ester anhydride); combination thereof.

In some examples or embodiments, the scaffolds and other components ofthe stents and endoluminal prostheses may be coated for variouspurposes, including coating to prevent sharp metal edges, as describedthroughout this application, and/or where coating material comprises, orcomposed from: polyaryletherketone; polyetheretherketone; polyimide,polyethylene such as UHMW, HDPE, LDPE, or others; polypropylene;polyester; polyethylene terephthalate; polycarbonate; polysulfone;polyphenylsulfone; polyethersulpone, Ultem; polyetherimide;polyurethane; polyamide; nylon such as nylon 12, nylon 6, nylon 6-6, orothers; polyvinylchloride; PTFE; FEP; ETFE; PFA; PVDF;polyvinylchloride; acrylobutadiene styrene; Delrin;polymethylmethacrylate; polystyrene; polyacrylamide, polyphenylsufide;PEBAX; terpolymer, blends, mixes, or combination thereof of lactides,caprolactones, trimethylene carbonate, and or glycolides such aspolylactide, poly(L-lactide), poly-DL-Lactide, polylactide-co-glycolide(e.g., poly(L-lactide-co-glycolide) with 85% L-lactide to 15%glycolide), copolymer of poly(L-lactide-co-epsilon-caprolactone (e.g.,weight ratio of from around 50 to around 95% L-lactide to about 50 toabout 5% caprolactone; poly (L-lactide-co-trimethylene carbonate),polytrimethylene carbonate, poly(glycolide-trimethylene carbonate),poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids; protein such as elastin, fibrin, collagen,glycoproteins, gelatin, or pectin; poly-serine; polycaprolactam;cyclodextrins; polysaccharides such as chitosan, and hyaluronan;alginate; polyketals; fatty acid-based polyanhydrides, amino acid-basedpolyanhydrides; poly(ester anhydride); combination thereof, or the like.

In one example, corrodible or degradable metallic or metallic alloymaterial comprising metal or metal alloy of Nickel; Cobalt; Tungsten andTungsten alloys; Tungsten alloys of rhenium, cobalt, iron, zirconium,zinc, titanium; Magnesium, Magnesium alloy AZ31, magnesium alloy withless than 20% zinc or aluminum by weight, without or with one or moreimpurities of less than 3% iron, silicone, manganese, cobalt, nickel,yttrium, scandium or other rare earth metal; zinc or its alloy; bismuthor its alloy; indium or its alloy, tin or its alloy such as tin-lead;silver or its alloy such as silver-tin alloy; cobalt-iron alloy; iron;iron containing alloys such as 80-55-06 grade cast ductile iron, othercast ductile irons, AISI 1010 steel, AISI 1015 steel, AISI 1430 steel,AISI 8620 steel, AISI 5140 steel, or other steels; melt fusible alloys(such as 40% bismuth-60% tin, 58% bismuth-42% tin, bismuth-tin-indiumalloys; alloys comprising one or more of bismuth, indium, cobalt,tungsten, bismuth, silver, copper, iron, zinc, magnesium, zirconium,molybdenum, indium, tin; or other material; or the like.

In another example, suitable materials including suitable stent materialincluding polymeric and metallic (degradable or non-degradable),adhesives, coatings, solder, sleeves, sealants, sealants, pottingcompounds, fixation materials, cement, energy fixation, elastomers andother type material, include but are not limited to: adhesives such ascyanoacrylate such as polyalkyl-2-cyanoacrylate, methyl-2-cyanoacrylate,ethyl-2-acrylate; n-butyl cyanoacrylate, 2-octyl cyanoacrylate, orothers; gorilla glue; lysine based adhesive such as TissueGlu, SylysSurgical Sealant, or others; fibrin glue; beeswax. Non-degradableadhesives, sealants, and potting compounds such as epoxy; epoxamine;UV-curable from Loctite, Dymax, Master Bond, or other; acrylic;silicone; hot melt; polyurethane; Degradable sleeve materials, stentmaterial, and coatings such as polyester; polylactide and theircopolymers and blends; copolymers of lactide, caprolactone, trimethylenecarbonate, glycolide; poly(L-lactide), poly-DL-Lactide,polylactide-co-glycolide (e.g., poly(L-lactide-co-glycolide); copolymerof poly(L-lactide-co-epsilon-caprolactone (e.g., weight ratio of fromaround 50 to around 95% L-lactide to about 50 to about 5% caprolactone;poly (L-lactide-co-trimethylene carbonate; polytrimethylene carbonate;poly-caprolactone; poly(glycolide-trimethylene carbonate);poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids; protein such as elastin, fibrin, collagen,glycoproteins, gelatin, or pectin; poly-serine; polycaprolactam;cyclodextrins; polysaccharides such as chitosan, and hyaluronan;alginate; polyketals; fatty acid-based polyanhydrides, amino acid-basedpolyanhydrides; poly(ester anhydride); polymer blends; and/orco-polymers; or combination thereof; or the like. Corrodible solder orfusible alloy such as Sn97Cu3, Sn50Zn49Cu1, Sn95.5Cu4Ag0.5, Sn90Zn7Cu3,Sn98Ag2, Sn96.5Ag3Cu0.5, Sn91Zn9, Sn85Zn15, Sn70Zn30, Sn89Zn8Bi3,Sn83.6Zn7.6In8.8, Sn86.9In10Ag3.1, Sn95Ag3.5Zn1Cu0.5,Sn86.5Zn5.5In4.5Bi3.5, Sn95Sb5, Sn96.2Ag2.5Cu0.8Sb0.6, Sn90Au10, orothers; Indium or its alloy such as In97Ag3, In90Ag10, In50Sn50,In52Sn48, or others; zinc or its alloy such as Zn95A15, Zn60Sn40,Zn95Sn5, or others; bismuth or its alloy such as Bi57Sn42Ag1, Bi58Sn52,or others. Non-corrodible solder or fusible alloy such as gold or itsalloy such as Au80Sn20, Au98Si2, Au87.5Ge12.5, Au82In18. Degradable andnon-degradable polymers include: polyester; polylactide and theircopolymers and blends; copolymers of lactide, caprolactone, trimethylenecarbonate, glycolide; poly(L-lactide), poly-DL-Lactide,polylactide-co-glycolide (e.g., poly(L-lactide-co-glycolide); copolymerof poly(L-lactide-co-epsilon-caprolactone (e.g., weight ratio of fromaround 50 to around 95% L-lactide to about 50 to about 5% caprolactone;poly (L-lactide-co-trimethylene carbonate; polytrimethylene carbonate;poly-caprolactone; poly(glycolide-trimethylene carbonate);poly(lactide-glycolide-trimethylene carbonate) or the like;polyhydroxybutyrate such as poly(3-hydroxybutyrate) andpoly(4-hydroxybutyrate); polyhydroxyvalerate;polyhydroxybutyrate/polyhydroxyvalerate copolymers (PHV/PHB);polyhydroxyalkanoate; poly orthoesters; poly anhydride;polyiminocarbonate; tyrosine-derived polycarbonate; tyrosine-derivedpolyacrylate; iodinated and/or brominated tyrosine-derivedpolycarbonate; iodinated and/or brominated tyrosine-derivedpolyacrylates polyesteramide; polycarbonate copolymer, lactone basedpolymers such as poly(propylene fumarate-co-ethylene glycol) copolymer(aka fumarate anhydride); polyanhydride esters; polyorthesters;silk-elastin polymer; polyphosphazene; aliphatic polyurethane;polyhydroxy acid; polyether ester; polyester; polydepsidpetide;poly(alkylene oxalates); polyaspartimic acid; polyglutarunic acidpolymer; poly-p-dioxanone; poly-beta-dioxanone; asymmetrically3,6-substituted poly-1,4-dioxane-2,5-diones; polyalkyl-2-cyanoacrylates;polydepsipeptides (glycine-DL-lactide copolymer); polydihydropyranes;polyalkyl-2-cyanoacrylates; poly-beta-maleic acid (PMLA); polyalkanotes;poly-beta-alkanoic acids; protein such as elastin, fibrin, collagen,glycoproteins, gelatin, or pectin; poly-serine; polycaprolactam;cyclodextrins; polysaccharides such as chitosan, and hyaluronan;alginate; polyketals; fatty acid-based polyanhydrides, amino acid-basedpolyanhydrides; poly(ester anhydride); polymer blends; and/orco-polymers; or combination thereof; or the like. polyvinyl alcohol;polyvinyl acetate; ethylene-vinyl acetate (a hot-melt glue); phenolformaldehyde resin; polyamide such as nylon 12, nylon 6, nylon 6-6, orothers; polyester resins; polyethylene (a hot-melt glue), UHMW, HDPE,LDPE, or others; polychloroprene; polyaryletherketone;polyetheretherketone; polypropylene; polystyrene; polyester;polyethylene terephthalate; polycarbonate; polysulfone;polyphenylsulfone; polyethersulpone, Ultem; polyetherimide;polyurethane; polyvinylchloride; PTFE; FEP; ETFE; PFA; PVDF;polyvinylchloride; acrylobutadiene styrene; polyacetal such as Delrin;polymethylmethacrylate; polystyrene; polyacrylamide, polyphenylsufide;PEBAX; and/or co-polymers, and/or combination thereof. Elasticnon-absorbable polymeric or elastomers such as silicone rubber; C-flex;poly(n-butylmethacrylate); poly(n-butylmethacrylate) blended withpoly(methamethacrylate), Poly(hexyl methacrylate), andpolyvinylpyrrolidone; Kraton; poly(styrene-ethylene/butylene-styrene)(SEBS); poly(styrene-ethylene/propylene-styrene) (SEPS), poly(acrylicacid-b-styrene-b-isobutylene-b-styrene-b-acrylic acid;poly(styrene-b-isobutylene-b-styrene); polybutadiene; PVDF-HFPpoly(vinylidene fluoride-hexafluorpropylene); polyvinylpyrrolidone;poly(ethylene-co-vinyl acetate); phosphorylcholine; PEBAX; polyurethaneelastomers; Tecoflex; Biomer; Pellethane; corethane; silicone rubber;rubbers; elastomers; blends; copolymers; combination thereof; or thelike. Non-corrodible elastic metal or metal alloys such as shape or heatmemory alloy, shape memory polymer, or superelastic materials, typicallya nickel-titanium alloy; a spring stainless steel; Ni50-Mn28-Ga22;copper-aluminium-nickel; alloys of zinc, copper, gold and iron;iron-based alloy such as Fe—Mn—Si; copper-based alloy such as Cu—Zn—Aland Cu—Al—Ni; or the like. Metals or metal alloys that have high initialstrength and weaken over time include Ti6A14V, Ti5Al2.5Sn, orTi-10V-Fe-3Al; stainless steel such as SAF2507; zinc alloys such asZn5al, Zn10Al, Zn18Al, Zn30Al, platinum metal and its alloys; tin alloyssuch as Sn3.9Ag0.6Cu, Sn-3.8Ag-0.7Cu, SnPb, or SnPbAt; aluminum alloyssuch as A11.7Fe, A10.7Cu, A1.5MgScZr, Al6Mg0.2Sc0.15Zr, 3004, 8090,7075, 6061, or 5056; zirconium alloy such as Zr55A110Ni5Cu30; magnesiumalloy such as AZ31B or MG11li5A11Zn0.034Sc (LAZ1151); iron alloy such asFe29.7Mn8.7Al1C, 30HGSA alloy steel, 4140, C45 steel, Fe36Ni, or lowcarbon steel; Nickel Alloys such as Ni21Cr17Mo or Haynes 230.Non-corrodible (non-degradable) metals or metal alloys such asconventional titanium alloys such as Ti6A14V, Ti5Al2.5Sn, orTi-10V-Fe-3Al; stainless steel such as SAF2507; platinum metal and itsalloys; aluminum alloys such as A11.7Fe, A10.7Cu, A1.5MgScZr,Al6Mg0.2Sc0.15Zr, 3004, 8090, 7075, 6061, or 5056; zirconium alloy suchas Zr55A110Ni5Cu30; 304V, 304L, and 316LV stainless steel; steel alloysuch as mild steel; cobalt based alloy such as cobalt chrome; L605,Elgiloy, Phynox; platinum based alloy such as platinum chromium,platinum iridium, and platinum rhodium; tin based alloys; rhodium;rhodium based alloy; palladium; palladium base alloy; aluminum basedalloy; titanium or their alloy; rhenium based alloy such 50:50 rheniummolybdenum; molybdenum based alloy; tantalum; gold or their alloy;silver or their alloy; shape memory metal or alloy; chromium basedalloy; nickel-titanium alloy such as linear-elastic and/or super-elasticnitinol; nickel alloy such as nickel-chromium-molybdenum alloys (e.g.,INCONEL 625, Hastelloy C-22, Hatelloy C276, Monel 400, Nickelvac 400,and the like); nickel-cobalt-chromium-molybdenum alloy such as MP35-N;Nickel Alloys such as Ni21Cr17Mo or Haynes 230; or other;nickel-molybdenum alloy; platinum enriched stainless steel; combinationthereof; or the like. Corrodible metals or metal alloys (degradable)include nickel, cobalt, tungsten; tungsten alloys of rhenium, cobalt,iron, zirconium, zinc, titanium; magnesium, magnesium alloys, magnesiumalloy AZ31, magnesium alloy with less than 20% zinc or aluminum byweight, without or with one or more impurities of less than 3% iron,silicone, manganese, cobalt, nickel, yttrium, scandium or other rareearth metal, AZ31B or MG11li5A11Zn0.034Sc (LAZ1151); zinc or its alloysuch as zinc alloys such as Zn5al, Zn10Al, Zn18Al, Zn30Al; bismuth orits alloy; indium or its alloy, tin or its alloy such as tin-lead,Sn3.9Ag0.6Cu, Sn-3.8Ag-0.7Cu, SnPb, or SnPbAt; silver or its alloy suchas silver-tin alloy; cobalt-iron alloy; iron or its alloys such as80-55-06 grade cast ductile iron, other cast ductile irons, AISI 1010steel, AISI 1015 steel, AISI 1430 steel, AISI 8620 steel, AISI 5140steel, Fe29.7Mn8.7Al1C, 30HGSA alloy steel, 4140, C45 steel, Fe36Ni, lowcarbon steel or other steels; melt fusible alloys (such as 40%bismuth-60% tin, 58% bismuth-42% tin, bismuth-tin-indium alloys; alloyscomprising one or more of bismuth, indium, cobalt, tungsten, bismuth,silver, copper, iron, zinc, magnesium, zirconium, molybdenum, indium,tin; or other material; or the like. Other non-degradable polymericmaterial includes Parylene, and C-flex.

In further examples or embodiments, the body of the device, or thestent, or the material comprising the body of the device, or thematerial comprising one or more layers of the body of the device,comprises one or more biologically active agents. In some embodiments,the biologically active agent(s) are selected from the group consistingof anti-proliferative agents, anti-mitotic agents, cytostatic agents,anti-migratory agents, immunomodulators, immunosuppressants,anti-inflammatory agents, anticoagulants, anti-thrombotic agents,thrombolytic agents, anti-thrombin agents, anti-fibrin agents,anti-platelet agents, anti-ischemia agents, anti-hypertensive agents,anti-hyperlipidemia agents, anti-diabetic agents, anti-cancer agents,anti-tumor agents, anti-angiogenic agents, angiogenic agents,anti-bacterial agents, anti-fungal agents, anti-chemokine agents, andhealing-promoting agents. In certain embodiments, the body of the devicecomprises an anti-proliferative agent, anti-mitotic agent, cytostaticagent or anti-migratory agent. In further embodiments, the body of thedevice comprises an anticoagulant, anti-thrombotic agent, thrombolyticagent, anti-thrombin agent, anti-fibrin agent or anti-platelet agent inaddition to an anti-proliferative agent, anti-mitotic agent, cytostaticagent or anti-x migratory agent. It is appreciated that specificexamples of biologically active agents disclosed herein may exert morethan one biological effect.

Examples of anti-proliferative agents, anti-mitotic agents, cytostaticagents and anti-migratory agents include without limitation inhibitorsof mammalian target of rapamycin (mTOR), rapamycin (also calledsirolimus), deuterated rapamycin, TAFA93, 40-O-alkyl-rapamycinderivatives, 40-O-hydroxyalkyl-rapamycin derivatives, everolimus{40-O-(2-hydroxyethyl)-rapamycin}, 40-0-(3-hydroxy)propyl-rapamycin,40-O-[2-(2-hydroxy)ethoxy]ethyl-rapamycin, 40-O-alkoxyalkyl-rapamycinderivatives, biolimus {-40-O-(2-ethoxyethyl)-rapamycin},40-O-acyl-rapamycin derivatives, temsirolimus{-40-(3-hydroxy-2-hydroxymethyl-2-methylpropanoate)-rapamycin, orCCI-779}, 40-O-phospho-containing rapamycin derivatives, ridaforolimus(40-dimethylphosphinate-rapamycin, or AP23573), 40 (R orS)-heterocyclyl- or heteroaryl-containing rapamycin derivatives,zotarolimus {-40-epi-(N1-tetrazolyl)-rapamycin, or ABT-578},40-epi-(N2-tetrazolyl)-rapamycin, 32 (R or S)-hydroxy-rapamycin,myolimus (32-deoxo-rapamycin), novolimus (16-O-desmethyl-rapamycin),AP20840, AP23464, AP23675, AP23841, taxanes, paclitaxel, docetaxel,cytochalasins, cytochalasins A through J, latrunculins, and salts,isomers, analogs, derivatives, metabolites, prodrugs and fragmentsthereof. The IUPAC numbering system for rapamycin is used herein. Incertain embodiments, the body of the device comprises myolimus ornovolimus. Other drugs include vasoactive agents including vas-dilatorsand vaso-constrictors, comprising for example, Methergin, acetylcholine,and Nitroglycerine, their analogues, derivatives, and metabolite, toname a few.

Other specific drugs suitable for use on the scaffolds and in themethods of the present invention are described in commonly assigned U.S.Pat. No. 9,119,905, the full disclosure of which is incorporated hereinby reference.

VI. Stents Having Helical Backbones

Referring now to FIG. 36, a prior art helical stent 1300 comprises ascaffold having a helical backbone 1302. The helical backbone 1302comprises a plurality of adjacent turns (rings) 1304 where individualturns comprise crowns 1306 joined by struts 1308. In prior art stents,at least some of the adjacent turns in such helical stents may joined bypermanent axial connectors 1310. The helical backbone is typicallyformed by bending wire around a mandrel, and the axial connectors 1310are typically formed by welding or otherwise fusing the adjacent turnstogether at points where opposed crowns 1306 lie immediately adjacent toone another.

Referring now to FIG. 37, a helical stent scaffold 1312 constructed inaccordance with the principles of the present invention comprises aplurality of turns (rings) 1314 having crowns 1316 and struts 1318.Adjacent crowns may be connected by a separation region 1320 which maybe formed as any of the separation regions described elsewhere in thisapplication. Conveniently, when convex regions of axially opposed crowns1316 lie closely adjacent to each other, as shown in FIG. 37, the crownsmay be joined by a bio-degradable adhesive, a link, or other material1316 or structure which bridges the gap therebetween. The bio-degradableadhesive, a link, or other material 1316 will be configured to separateafter implantation of the stent scaffold 1312 by any of the separationmechanisms described elsewhere herein. Alternatively or in addition toseparation regions 1320 between successive turns 1314, the stentscaffold 1312 may have separation regions 1320 a and 1320 b in at leastsome of the struts 1318 and crowns 1316, respectively. Depending on theparticular pattern of separation regions 1320, 1320 a, and 1320 b whichis selected, the stent scaffold 1312 may be able to expand and contractby forming discontinuities in the separation regions located on at leastsome circumferential turns (in struts or crown regions), and/ordeformation of the rings, e.g. opening of the crowns, and/or byunwinding of the helical backbone of the stent.

Referring now to FIG. 38, another helical stent scaffold 1322 maycomprise a plurality of turns (rings) 1324 including crowns 1326 andstruts 1328 where adjacent crowns 1326 may be joined a bridging segment1330 which wraps around the crowns. Such bridging segment may be formedfrom a bio-degradable or other frangible material as described elsewhereherein in accordance of the principles of the present invention. As withstent scaffold 1312, stent scaffold 1322 may have additional separationregions in at least some of the struts and crowns (not illustrated),respectively. Depending on the particular pattern of separation regionswhich is selected, the stent scaffold 1322 may be able to expand andcontract by forming discontinuities in the separation regions located onat least some circumferential turns (in struts or crown regions), and/ordeformation of the rings, e.g. opening of the crowns, and/or byunwinding of the helical backbone of the stent.

As shown in FIGS. 36-38, the crowns of each successive turn (rings) ofthe scaffold are “out-of-phase” so that the convex surfaces of at leastmost of the crowns are axially opposed and in contact or separated by avery short gap. Referring now to FIG. 39, a helical stent scaffold 1332may comprise adjacent turns 1334 where the crowns 1336 and struts 1338are “in phase” so that an axial connector 1340 may span between a convexside of one crown and extend into a concave side of the adjacent crown.The connector 1340 comprises a separation region 1341 which may beformed as any of the separation regions described elsewhere in thepresent application. However, the separation region 1341 typically willnot be sufficient to uncage the circumferential turns (or rings), butrather having one or more separation regions in the strut and/or crownregions (not shown) of each of the turns are needed to circumferentiallyuncage the turns (rings).

Referring now to FIG. 40, a helical stent scaffold 1342 comprises aplurality of turns 1324, at least some of which will be “in phase” asdescribed previously with reference to FIG. 39. Instead of extendingfrom a convex side of one crown to a concave side of another crown,connectors 1350 may extend between the convex sides of two“out-of-phase” crowns 1346 as illustrated. Again, the connector 1350includes a separation region 1351 which may comprise any of theseparation regions described elsewhere herein. However, the separationregion 1351 typically will not be sufficient to uncage thecircumferential turns (or rings), but rather having one or moreseparation regions in the strut and/or crown regions (not shown) of eachof the turns are needed to circumferentially uncage the turns (rings).

As shown in FIG. 41, a helical stent scaffold 1352 comprising turns 1354having crowns 1356 and struts 1358 may comprise a connector 1360 whichextends between axially spaced-apart struts 1358. Again, the connector1360 includes a separation region 1361 which may comprise any of theseparation regions described elsewhere herein. However, the separationregion 1361 typically will not be sufficient to uncage thecircumferential turns (or rings), but rather having one or moreseparation regions in the strut and/or crown regions (not shown) of eachof the turns are needed to circumferentially uncage the turns (rings).

Finally, as illustrated in FIG. 42, a helical stent scaffold 1362 maycomprise turns 1364 having struts 1336 and crowns 1368 where a connector1370 extends between a convex side of one crown 1368 to an adjacentstrut 1366. Again, the connector 1370 includes a separation region 1371which may comprise any of the separation regions described elsewhereherein. However, the separation region 1371 typically will not besufficient to uncage the circumferential turns (or rings), but ratherhaving one or more separation regions in the strut and/or crown regions(not shown) of each of the turns are needed to circumferentially uncagethe turns (rings).

As with stent scaffold 1312, stent scaffolds 1332, 1342, 1352, and 1352may have additional separation regions in at least some of the strutsand crowns (not illustrated), respectively. Depending on the particularpattern of separation regions which is selected, each of the stentscaffolds may be able to expand and contract by having one or moreseparation regions in at least some turns (in crown or strut regions),and/or deformation of the rings, e.g. opening of the crowns, and/or byunwinding of the helical backbone of the stent.

VII. Circumferentially Linked Closed Cell Stents

The separation region technology of the present invention may also beapplied to closed cell scaffolds on stents and other luminal prostheses.For example, as shown in FIG. 43, a closed cell stent scaffold 1400comprises a plurality of circumferential rings 1402. Each ring comprisesa number of quadrangular closed cells 1404 joined by axial links 1406.The quadrangular closed cells 1404 within each circumferential ring 1402are joined by circumferential connectors 1408.

In accordance with the present invention, separation regions 1410 and1411 are formed in at least some of the circumferential rings 1402 inorder to enhance compliance of the scaffold after the scaffold isimplanted in a blood vessel or other body lumen. For example, separationregions 1410 may be located in one or more of the circumferentialconnectors 1408 allowing adjacent quadrangular closed cells 1404 tocircumferentially separate in response to physiologic forces afterimplantation. Alternatively, separation regions 1411 may be locatedwithin the struts or other elements of the quadrangular closed cellsthemselves. Typically, the circumferential rings 1402 of the scaffold1400 are joined by axially aligned links 1406 or other elements whichtypically remain intact after the separation regions formdiscontinuities.

Another closed cell scaffold 1416 is illustrated in FIG. 44 and includes“closely packed” quadrangular cells 1418, where each cell has serpentineor “wavy” axial elements 1424 and transversely oriented end elements1420. The end segments 1420 will typically comprise a separation region1426 in order to enhance circumferential compliance of the stent afterimplantation. However, separation regions 1427 formed in the axialelements 1424 alone typically will not uncage the scaffoldcircumferentially. The separation regions 1426 and/or 1427 may be any ofthe types of separation regions described elsewhere in the presentapplication.

A closed-cell stent scaffold 1430 illustrated in FIG. 45 comprises aplurality of closely packed diamond-shaped cells 1432. Separationregions 1438 may be provided in the circumferential connectors of thediamond-shaped cells 1432. Alternatively, separation regions 1439 may beprovided in the strut elements of the diamond-shaped closed cells 1432.

In yet another example as shown in FIG. 46, a closed cell stent scaffold1450 comprises diamond-shaped cells 1452 which are defined by struts1453 which cross each other at junctions 1454. Separation regions 1456may be provided at the junctions 1454 and/or separation regions 1457 maybe provided in the struts 1453 between junctions. Such closed cell stentscaffold 1450 with diamond-shaped cells are typically patterned by lasercutting or etching from a tubular base structure in a conventionalmanner. The separation regions may then comprise any of the separationregions described elsewhere herein.

In a still further example as shown in FIGS. 46A and 46B, a stentscaffold 1460 comprises zig-zag circumferential rings 1462 (or may alsobe other patterns such as serpentine rings) which are formed by struts1464 which are joined at crowns 1466. Some, but not all axially adjacentcrowns in axially adjacent rings 1462 are joined into four-way junctionsthat join the adjacent rings. The junctions 1468 will act as separationregions, or maybe configured to be a separation region, and can beformed to form discontinuities, break or bisect at locations 1470 toallow circumferential separation of the rings, as shown in FIG. 46B. Inthis way, adjacent rings 1462 will remain axially joined while they arecircumferentially released (or to increase circumferential compliance asdescribed elsewhere herein. The junctions 1468 may be formed in any ofthe ways described previously, e.g. having preformed breaks joined bydegradable sleeves or adhesives, being weakened regions which break inresponse to fatigue caused by luminal pulsation, or other, or the like.

In FIG. 47, a scaffold 1600 comprises a plurality of circumferentialrings 1602 attached to an axially oriented backbone 1604. Each ring hasa gap 1606, where the gaps in at least some of the successive rings arerotationally staggered relative to each other. The purpose of therotational staggering is to more uniformly distribute thecircumferential support while maintaining the elasticity provided by thegap. That is, in designs where the gaps are axially aligned, thecircumferential support will be diminished along the side where the gapsare aligned. Such diminished support is reduced or eliminated bystaggering the gaps. As illustrated, the gaps 1606 in successive ringsare rotationally staggered by 90°, but the degree and pattern ofstaggering can be varied so long as the circumferential support ismaintained. As a further alternative, not illustrated, the scaffold 1600could have two, three, or more axial backbones, either in parallel,located in successive axial regions of the scaffold.

In FIG. 48, a scaffold 1620 comprises a plurality of circumferentialrings 1602 axially joined by a plurality rotationally staggered links orbackbone segments 1624. The plurality segments or links 1624 replace thebackbone 1604 of FIG. 47 and maintain the axial integrity of thescaffold 1620. Although a single link or segment 1624 is shown betweeneach successive pair of rings 1622, it will be appreciated that two,three or more segments or links could be located between at least someof the adjacent rings 1622, As with scaffold 1600, each ring 1622 inscaffold 1620 has a gap 1626, where the gaps in at least some of thesuccessive rings 1622 are rotationally staggered relative to each other.The purpose of the rotational staggering is the same as with scaffold1620, i.e. to more uniformly distribute circumferential support whilemaintaining the elasticity provided by the gap. As illustrated, the gaps1626 are located 180° in opposition to the attachment location of atleast one segment or link 1624, but other orientations would also finduse.

The stent scaffolds 1600 and 1620 may be formed from any of thematerials and by any of the fabrication protocols described elsewhereherein. In particular, the scaffolds may be formed by patterning a metalor other tube. Alternatively, the scaffolds could be formed by bendingone or more wires into the illustrated patterns, e.g. by bending asingle wire into the pattern, turning the wire at one end, and thenbending the wire back in a pattern parallel to the previously bent wire.

In one example to measure Vasomotion (constriction or dilation), stentcontraction and/or expansion, vessel enlargement, or other tests, inhumans or porcine model can be as follows: In a porcine model, aninfusion catheter is passed through the guiding catheter and positionedproximal to the site of device implantation. Using a syringe pump,incremental dose levels of acetylcholine (10⁻⁷, 10⁻⁶, and 10⁻⁵ M) areslowly administered (1.0 ml/min over 3 min), as needed, with a minimum5-min washout period between each dose. The blood pressure and heartrate are monitored during each infusion to prevent acetylcholine-inducedischemia. The incremental dosing regimen is discontinued when theconstriction is visually distinct and the subsequent dose would mostlikely induce an ischemic event. Angiographic images are acquired priorto and after each dose to capture the effects of acetylcholine foroff-line QCA measurements. Following the effective dose of acetylcholineinfusion, a bolus of nitroglycerin (300 mg) is administered to assessthe vasodilatory response, and an angiogram is captured for off-line QCAanalysis. In the case of acetylcholine infusion, a vasoconstriction inthe distal non-device implanted segment would result in reduced contrastflow in the distal segment as well as the device implanted segment dueto reduced blood flow resulting in an artifactual reduction in thevessel diameter in the device implanted segment. To avoid this artifact,the lumen diameter at the midsection of the device implanted segment waschosen for all analysis for better accuracy. As for humans, measure meanlumen diameters by QCA after baseline saline infusion and sub-selectiveintracoronary administration of acetylcholine infused through amicrocatheter at increasing dose from 10⁻⁸ M to 10⁻⁶ M. For methergintest, QCA is measured 5 min after intravenous bolus injection ofmethergin (0.4 mg). Both tests are terminated by intracoronaryadministration of 200 μg of nitroglycerin. The change in the lumendiameter following the treatment with the vasoactive substance ismeasured using off-line end-diastolic QCA angiographic acquisitionsduring pre-dose, post-acetylcholine or methergin, and post nitroglycerininfusions. A sub-segment analysis of the artery is performed todetermine the mean lumen diameter (MLD) changes of the device implantedsegments and the 5-mm proximal and distal edges. Absolute MLDdifferences (deltas) (post-infusion−pre-infusion) is assessed as well asrelative percentage MLD changes(post-infusion−preinfusion/re-infusion×100%). The data providesmeasurements and magnitude of the implanted device and/or vessel toundergo vasomotion (vasodilation and/or vasoconstriction), expansion ofthe stent, and/or contraction of the stent, and/or enlargement of thestented vessel segment, and/or contraction of the stented vesselsegment. An example for evaluation of vasomotion by IVUS:Vasomotioncould also be assessed in porcine model and humans through measurementof lumen areas by IVUS preferably in a mid-section of the deviceimplanted segment and/or the implanted segment of the artery arteries atthe same position in the end-diastolic and end-systolic state. Theabsolute difference in the lumen cross-sectional area observed fromsystole to diastole within the mid-section of the device implantedsegment (ALA) will provide the necessary information to evaluate theability and magnitude of the implanted device and/or vessel to undergovasomotion (vasodilation and/or vasoconstriction), expansion of thestent, and/or contraction of the stent, and/or enlargement of thestented vessel segment, and/or contraction of the stented vesselsegment.

VIII. Stent Prostheses Having Displacement Regions Such asCircumferential Displacement Regions.

FIG. 49 illustrates a single partial circumferential ring 1702 of astent prosthesis 1700 formed from struts 1704 and crowns 1706, where twoof the struts have displacement regions such as circumferentialdisplacement regions 1710 constructed in accordance with the principlesof the present invention. The circumferential partial ring 1702 isconnected to axially adjacent circumferential rings (not fully shown) byaxial links 1708. In contrast to the separation regions describedpreviously, these displacement regions 1710 may be configured to providean elastic region for expanding and/or contracting the circumferentialdimension of a circumferential ring, not just separation as previouslydescribed.

FIG. 50 is a perspective view of the circumferential displacement region1710 shown with a male terminal or attachment region 1712 on a strutsegment 1704 separated from a female terminal or attachment region 1714formed as a fork or clevis at the terminal end of an adjacent strutsegment 1704. An opening or cavity 1715 in the female attachment region1714 is oversized compared to the width of the male region 1712 of strut1704, as best seen in FIG. 51, to create a buffer zone 1713 between themale and female attachment regions. The broken lines in FIG. 51 indicatethe range of lateral motion available to the male attachment region 1712of strut 1704, which allows the strut to move in the directions of thearrows shown in FIG. 51. FIG. 52 shows that the male attachment region1712 is also able to move up and down relative to a horizontal plane ofthe strut 1704, also as shown in broken line and indicated by the arrowsof FIG. 52. While similar “lock-and-key” separation regions have beenshown previously in this application, when used as a circumferentialdisplacement region, the free space or buffer region between the outersurfaces of the male elements 1712 and the inner surfaces of the femaleregion 1714 will generally be greater to allow more freedom of movement.

Referring now to FIGS. 53 and 54, the buffer zone 1713 between the outersurfaces of the male element 1712 and the inner surfaces of the femaleelement 1714 may optionally be filled with an elastic cushion material1716. Suitable cushion materials include but are not limited tosilicones, silicone rubber; C-flex; poly(n-butylmethacrylate);poly(n-butylmethacrylate) blended with poly(methamethacrylate),Poly(hexyl methacrylate), and polyvinylpyrrolidone; Kraton;poly(styrene-ethylene/butylene-styrene) (SEBS);poly(styrene-ethylene/propylene-styrene) (SEPS), poly(acrylicacid-b-styrene-b-isobutylene-b-styrene-b-acrylic acid;poly(styrene-b-isobutylene-b-styrene); polybutadiene; polyisoprene;Polystyrene butadiene rubber (SBR), Polyethylene-propylene-diene (EPDM);PVDF-HFP poly(vinylidene fluoride-hexafluorpropylene);polyvinylpyrrolidone; poly(ethylene-co-vinyl acetate);phosphorylcholine; PEBAX; polyurethane elastomers; Tecoflex; Biomer;Pellethane; corethane; silicone rubber; rubbers; natural rubbers;elastomers; blends; copolymers; combination thereof; or the like. Thecushioning materials will typically adhere to both the male attachmentregion 1712 and the female attachment region 1714 so that the cushionmaterials will usually provide a permanent or long term interconnection.The elastic nature of the material, however, allows the cushion to actas an elastic connector to provide a controlled, elastic interactionbetween the two adjacent strut segments 1704.

As shown in FIG. 55, in some cases, two butt ends of adjacent strutsegments 1704 may be directly connected with a region 1720 of elasticmaterial which acts to elastically link the two struts together, servingas an elastic displacement region.

Referring now to FIGS. 56, 57, and 58A and 58B, a further embodiment ofa displacement regions such as circumferential displacement region 1710comprises a strut segment 1704 having a female attachment region 1720with a channel 1718 formed over a top surface. A male attachment region1722 is formed at the end of an adjacent strut segment 1704 andconfigured to be received in the channel 1718, as best seen in FIGS. 57and 58A, so that the strut may move laterally as well as upwardlyrelative to the strut end 1720. Downward movement of the strut end 1718,however, will be limited by the closed bottom of the channel 1718. Thegap or empty space between the strut end 1722 and the inner wall of thechannel 1718 may be empty (FIG. 58A) or may filled with an elasticmaterial 1728 (FIG. 58B), as generally described with prior examples orembodiments.

Referring now to FIGS. 59 and 60, a further example of a displacementregion constructed in accordance with the principles of the presentinvention will be described. A first strut segment 1704 has aclevis-type end region 714 with a pair of aligned holes or apertures1730 in the opposed walls of the clevis 1714. A male attachment end 1712of the other strut segment 1704 also has a hole 1732 formedtherethrough. Once the male end 1712 of the strut 1714 is in the femaleclevis 1714, as shown in FIG. 60, the pin 1726 may be passed through thealigned holes to provide for a pivoting arrangement. The gap between themale end 1712 and the interior of the female clevis 1714 may be open, asillustrated in FIG. 60, or may be filled with an elastomeric material asdescribed previously with other embodiments.

Referring now to FIGS. 61, 62A and 62B, an alternative stent structure1782 comprises a plurality of circumferentially ring 1784, where axiallyadjacent circumferential rings are joined by axial links 1790, as bestseen in FIG. 62A. The axial links 1790 will extend from a crown 1788 onone circumferential ring, while being attached to single strut 1789 onthe adjacent circumferential ring. The adjacent circumferential ring isfurther attached to the axial link 1790 by a cap 1792 which is receivedover a short pin 1794, as seen in FIG. 62A. This lock-and-key junctionallows displacement and flexibility between the adjacent circumferentialrings. While the presence of a short straight segment on the axial link1790 is shown in FIG. 62A, it will be appreciated that the link 1790could carry a female coupling element 1796 while the single strut 1789may terminate in the short pin element 1798, as shown in FIG. 62B. Theaxial link 1790 typically remains intact after formation ofdiscontinuity.

Referring now to FIG. 63, a stent prosthesis according to the presentinvention may be fabricated by forming two or more separate panels andthereafter joining those panels into a cylindrical stent structure. Asillustrated, a stent prosthesis 1760 may be fabricated by first formingseparate panels 1762, 1764 and 1766. The separate panels will typicallybe formed or patterned from a sheet of metal or polder material by wellknow laser cutting or chemical etching techniques. Each panel may, forexample, comprise a plurality of circumferential ring segments 1768,where each ring segment may further comprise struts and crowns asdescribed for many previous embodiments. In each panel, however, theends of the circumferential rings will terminate in an attachmentelement. In particular, as illustrated, some of the attachment elementsmay be male attachment elements 1770 and others may be female attachmentelements 1772. In particular, these may comprise the key-and-lockattachment elements described previously herein.

The attachment elements on each panel will be specifically arranged sothat the panels may be attached together for formation into the stentprosthesis. For example, the terminal ends of the circumferential ringsegments 1768 may have male and female attachment elements, while theadjacent terminal end on the adjacent panel would have a mating femaleor male element so that the elements may be joined.

As shown schematically in FIGS. 64A and 64B. The panels in 1764, 1766,and 1768 may be formed over a cylindrical mandrel 1776, and the terminalends of the individual circumferential ring segments then joined bycoupling elements 1778, as shown in FIGS. 64C and 64D. The couplingelements may be sleeves, adhesives, elastic cushion materials or thelike. Alternatively, the terminal ends of the circumferential ringsegments may be joined by mechanically interlocking the ends without anyfurther glue, adhesives, or filling materials.

Referring now to FIG. 65, the stent pattern of FIG. 61 may be modifiedto comprise three separate panels 1740, 1742, and 1744 which may befabricated into the stent in a manner similar to that described for64A-64D. In particular, each individual ring segment 1746 will terminatein a plurality of female attachment elements 1748 and male attachmentelements 1750 which are arranged to mate as the panels 1740, 1742, and1744 are brought together. Thus, the female attachment elements 1748 andmale attachment elements 1750 can act both as attachments points forassembling the complete stent prosthesis an as circumferentialdisplacement regions on the assembled stent prosthesis.

Referring now to FIGS. 66 and 67, a second alternative stent structure1800 has displacement regions 1802 formed on or adjacent to axial links1804 between adjacent circumferential rings 1806. The axial links 1804will extend from a crown 1810 on one circumferential ring, while beingattached to single strut 1812 on the adjacent circumferential ring. Theadjacent circumferential ring is further attached to the axial link 1804by a cap 1814 which is received over a disc 1816, as seen in FIG. 67.Such a “lock-and-key” junction allows displacement or discontinuity inthe circumferential ring.

Referring now to FIG. 84, an alternative stent structure 1900 hasseparation regions 1902 comprising interlocking combs with one or moreinterlocking teeth 1904. The interlocking combs allow control over thedirection of separation. While the separation regions are oriented at anangle α of about 60° relative to the circumference of the stent in thecrimped stent position (or 30° relative to the longitudinal axis of thestent), allowing them to resist separating when the stent is expandedfrom a crimped configuration to an expanded configuration. However,after expansion, the separation regions 1902 move toward acircumferential alignment, allowing the teeth 1904 of the comb to slidein and out of their position. The angle of the interlocking comb in thecrimped configuration can be from 0° to 75°, preferably be from 20° to65°, and more preferable be from 30° to 60°. The angle of theinterlocking comb separation regions in the expanded stent configurationcompared to the stent longitudinal length is approximately 90°, but canalso range from 65° to 120°, preferably ranges from 75° to 110°, morepreferably ranges from 80° to 100°. The separation region of this typepreferably are substantially aligned with the circumference of the stentin the expanded stent configuration.

Referring now to FIG. 85, stent structure 2000 comprises separationregions 2002 having a “lock- and key” structure with tapered geometry.As shown in broken line, the tapered geometry allows a greater lateralseparation between the male and female elements as the elements aredrawn apart than would be the case for non-tapered elements. Thisincreased lateral separation allows the struts and other structuralelements of the stent ring freer movement relative to each other in awide range of alignment, such as a keystone or trapezoidal shape. Thisallows for more forgiving movements of structural elements, preferablyin the circumferential direction, even when the structural elements arenot perfectly aligned in a circumferential direction. For example, ifthe taper on the keystone element is about 10°, the elements willcontinue to move in the circumferential direction easier (or morefreely) if they are aligned within 10° of the circumferential direction.Other shapes such as trapezoid shapes can also be beneficial.

Referring now to FIG. 86, an example of a prior art stent for valvereplacement showing the stent and stent pattern in FIG. 86A with thevalve in an open position, a top view of the stent with the valve in anopen position 86B, and a top view of the stent with the valve(tricuspid) in the closed position 86C. The valve is coupled to thestent, and a skirt covers at least one circumferential segment of thestent. The stent typically have one or more circumferential rings, havesinusoidal pattern, closed cell pattern, or combination pattern, orother. The stents are typically balloon expandable, or self-expandingstents prosthesis, can be retrievable or adjustable before implantation,and although can be deployed surgically, are typically inserted into thebody percutaneously, or introduced into the valve region via an atriumregion, a ventricle region such as apical approach, or a trans-septumapproach, for example. The valve can be bicuspid valve, a tricuspidvalve, or other types of valve. The valve to be replaced or repaired canbe the aortic valve, the mitral valve, the tricuspid valve, or othervalves in the body.

Referring now to FIGS. 87A-D, a stent 2100 for valve replacement (valvenot shown) has the stent pattern comprising one or more sinusoidal,circumferential rings. At least some of the one or more rings have oneor more separation regions, discontinuities, and/or joints, with fourlock-and-key separation regions 2102 being illustrated. The illustratedseparation regions 2102 are located symmetrically fashion about a singlering 2104 of the stent 2100. In other examples, however, the separationregions may be located asymmetrically, may be placed on more than onering, and may be positioned (or placed) in a variety of patterns alongthe circumferential path of one or more rings of the stent. In stillother examples, the separation regions may be placed on two or moreadjacent rings that are, two or more non-adjacent rings, on every otherring, on every third ring, or in other patterns. The separation regioncan be any of the types described in this application includingdiscontinuities, etc. In another example, as shown in FIG. 87D, one ormore hinges 2106 or other joints can be placed on at least one ring asdescribed above. Also, other types of joints can be utilized such asratchet, hinge, saddle, condyloid, ball and socket, plane, or other,etc. The stent prosthesis separation region or joints can be configuredin a variety of patterns where at least some of circumferential ringsseparation regions are aligned longitudinally (longitudinal stentlength) on adjacent rings, aligned in other type patterns, in order toachieve one or more of uncaging, changing in shape configuration,displacement direction and/or magnitude, of one or more rings, when thestent is in the expanded configuration. In one example, at least oneregion of the valve material is coupled to one separation region orjoint on the stent prosthesis. In another example, at least two valvematerial regions are coupled to two separation regions or joints on thestent prosthesis, in a third example, at least three valve regions arecoupled to three separation regions or joints on the stent prosthesis.In another example, at least one valve region is coupled (or connected)to a stent circumferential structural element adjacent to a separationregion or joint on the stent. In another example, at least one valvematerial region is connected to a circumferential structural elementabove and/or below a separation region or a joint on the stent ring(s).In another example, the valve material is substantially connected to onecircumferential ring having one or more separation regions or joints onthe stent. In another example, the valve material is substantiallyconnected to at least two circumferential rings having one or moreseparation regions or joints on the stent. In another example, the valvematerial is substantially connected to one circumferential ring adjacentto a ring having one or more separation regions or joints on the stent.The stent has sufficient strength in the expanded configuration tosupport a valve annulus or a body lumen. The stent can optionally havesupporting features such as those described in FIGS. 23C, 23D, or othertype of features to further enhance strength of the stent prosthesis inthe expanded configuration. The one or more separation regions and/orjoints on at least one ring (or circumferential element) of the stentprosthesis are configured to allow one or more of the following afterstent expansion to said at least one ring (or circumferential element)and/or to the stent: increase radial strain, increase radial strainwhile decreasing the strength from the initial deployed strength, changeof the radial strain magnitude after expansion of the stent, change ofthe strength magnitude after expansion of the stent, decrease instrength after expansion, change of the stent shape configuration,change of the displacement and/or magnitude in at least one direction,increase in the displacement in at least one direction, decrease in thedisplacement in at least one direction, preventing or minimizingvalvular leaks after implantation, preventing or minimizing valveregurgitation after implantation, change of the at least one ring shapeand/or the stent shape after expansion to one or more of: a tear dropshape configuration, an oblong shape configuration, an oval shapeconfiguration, a football shape configuration, a saddle type shapeconfiguration, a shape configuration contouring (or more fitting, ormore suited) to a valve annulus after stent expansion or after saidvalve annulus have changed shape configuration, other type shapeconfiguration. In one example, the at least one ring and/or the stent inthe expanded configuration has an initial shape, wherein the shapechanges after expansion, or after the valve annulus shape configurationchanges after stent expansion, or the at least one ring and/or stent inthe expanded configuration has an initial shape, wherein the shape issubstantially tubular, and wherein the shape configuration changes tosubstantially non tubular after expansion. The one or more separationregions and/or joints are configured as described throughout thisapplication, wherein said regions and/or joints are held together uponexpansion of the stent from a crimped configuration to an expandedconfiguration and wherein the separation regions and/or joints havediscontinuities and/or allowed to move in at least one direction afterexpansion, preferably in a time period ranging from 1 day to one yearafter expansion, more preferably in a time period ranging from 1 monthto 9 months after expansion. The means of holding the separation regionsand/or joints together to prevent movement or separation are describedthroughout this application. In another example, the separation regionsand/or joints are configured to not be held together upon expansion froma crimped configuration to an expanded larger configuration. In anotherexample, more typically where the stent prosthesis is patterned from ashape memory alloy, the stent continues to apply force against theannulus region potentially damaging it, or the stent does not conformwell to the shape of the annulus well causing some blood leakage, insuch example, the one or more separation region on at least one ring(and/or the stent) can help reduce such force and better conform to theannulus shape. The at least one ring and/or the stent strengthdecreases, thereby reducing the force on the annulus (or lumen). Theradial strain, displacement, and other parameters, have been previouslydescribed in the application. In one example, the stent prosthesis issecured to a fixation implant in the annulus or adjacent to the annulusto provide additional support or strength to the stent prosthesis afterat least some of the separation regions and/or joints havediscontinuities and/or are allowed to move.

Referring now to FIGS. 88A-88D, a stent 2120 for use in forming aprosthetic valve is constructed similarly to stent 2100 of FIGS.87A-87D. Instead of symmetrically spacing the separation regions 2122,however, stent 2120 has three separation regions 2122 clustered closelyon a single serpentine ring 2126, and the separation regions mayoptionally have hinges 2124 or other joints a shown in FIG. 88D. Havingseparation regions clustered around one or more stent segments (orregions) can be appreciated to perform one or more of the objectives ofthis invention.

Referring now to FIGS. 89A-89D, a closed cell stent 2130 for use informing a prosthetic valve has four lock-and-key separation regions 2132located symmetrically about a single ring 2134 of the stent 2130. Theseparation regions may optionally have hinges 2136 or other joints ashown in FIG. 89D.

Referring now to FIGS. 90A-90D, a stent 2140 for use in forming aprosthetic valve is constructed similarly to stent 2130 of FIGS.88A-88D. Instead of symmetrically spacing the separation regions 2142,however, stent 2122 has three separation regions 2142 clustered closelyon a single serpentine ring 2144, and the separation regions mayoptionally have hinges 2146 or other joints a shown in FIG. 90D.

Referring now to FIG. 91A, a fixation implant 2200 comprises one or morerings 2206 each having one or more joints 2204. The implant 2200 may becoupled to a valve annulus, adjacent to a valve annulus, above a valveannulus (superior), below a valve annulus (inferior), or somecombination thereof, for performing annuloplasty, implanting a valve, orfor any other purpose. Each ring in a stack of rings can have a similarshape and geometry, or two or more rings can have different shapes orgeometries, so long as the ring or rings are suitable for implantationwithin the annulus, the superior region to the annulus, or the inferiorregion to the annulus. The ring and/or stack of rings are configured toattach to the annulus, annulus tissue, or tissue adjacent to the annulusin a variety of ways such as sutures, clips, hooks, etc. Fixationelement 2202 may be provided on some or all of the rings, a plurality ofsuch elements may be provided along the length of the fixation implant.The fixation implant 2200 can be configured to receive (or to be coupledto) a valve or a stent containing a valve to replace the naturaldefective valve of the body (not shown in the drawings). The stent inone example can have at least one ring having one or more separationregions and/or joint. Alternatively, the fixation implant can be attachto (or be coupled with) the native valve, to one or more regions of thenative valve, attached to one or more regions adjacent to the valve orvalve region (such as chordae tendinese) to improve the function of thenative valve, to reduce regurgitation of the vale, and/or to reduceblood leakage of the valve. The fixation implant ring and/or stack ofrings are configured to have separation region and/or joints inaccordance with the principles of this application to allow one or moreof the following: shape configuration changes after implantation of saidring and/or stack of rings, to allow displacement in at least onedirection, or to allow displacement changes in at least one direction,to allow changes in displacement in D1 and D2 after implantation offixation implant, to allow increase radial strain, and other asdescribed in this application, as shown for a single ring in FIGS. 91Band 91C and for a three ring implant in FIGS. 91D and 91E.

The various figures illustrate some examples but are not limited to suchexamples, where the change in shape or displacement in x-axis, y-axis,orthogonal to the plane axis, or combination thereof, etc. Variousconfigurations of separation regions and/or joint are possible toachieve various shape type configurations, displacement direction anddisplacement magnitude, allowing the fixation implant to better conformto the annulus of the valve and/or the valve leaflets, and or a valveregion, such that the functionality of the valve is improved,regurgitation of the valve is minimized or prevented, and/or bloodleakage is minimized or prevented. The adaptive compliance,displacement, and/or shape configuration to the annulus, annulus valve,or tissue adjacent to the annulus, improves the functionality of thenative valve, after implantation of the fixation implant, and/or afterchange to the annulus shape, or configuration. In one example of thestackable configuration, the number of separation regions and/or jointscan be different or the same, the location of separation regions and/orjoints can be different or same, to allow for one or more of change inshape configuration, displacement in one or more direction, and/orradial strain of the fixation implant. Typically, the fixation implantis affixed to the tissue in a plurality of places to secure the fixationimplant to the said tissue, and wherein the shape configuration changes,displacement changes, or radial compliance changes occur about, oradjacent to, said separation regions and/or joint. In one example, thestackable rings can have varying shape changes configuration,displacement, and/or radial compliance, from one ring to an adjacentring. The ring and/or stackable rings can also be configured to receivea stent prosthesis for valve replacement. In one example, the ringand/or stackable rings can affect the shape, displacement, or radialcompliance of the stent as a result of ring and/or stackable ringchanges in shape, displacement, and/or compliance. Alternatively, thering and/or stackable rings can be adapted to receive a stent prosthesishaving one or more separation regions and/or joints. In this case, thering and/or stackable ring can amplify the shape changes, displacementmagnitude, and/or compliance of the stent prosthesis (and/or valvecontained within the stent prosthesis), or can further secure andprovide strength to the stent prosthesis. In one example the ringsand/or stackable rings are implanted percutaneously by having multiplefolding joints along the path of the circumferential length of the ring,wherein the joints when opened or expanded provide the ring in the openposition. Some of the joints are configured to be held in place onceopen while other are held in place while open and after implantation areconfigured to move or to have a displacement in one or more directions.Means to hold the separation regions and/or joints are describedelsewhere in this application.

Referring now to FIGS. 92A-92F, a fixation implant 2210 comprises onering 2212 (FIG. 92A) or three rings 2212 (FIG. 92B), each ring havingtwo diametrically opposed joints 2214. The implant 2210 may be coupledto a valve annulus, adjacent to a valve annulus, above a valve annulus(superior), below a valve annulus (inferior), or some combinationthereof, for performing annuloplasty, implanting a valve, or for anyother purpose. Each ring 2214 is capable of bending radially inwardlyand outwardly at each joint 2214, as shown in by arrows D1 and D2 inFIGS. 92C and 92D for a single ring and in FIGS. 92E and 92F for a threering stack. Fixation elements 2216 are usually provided on at last theterminal ring in each stack.

Referring now to FIGS. 93A-93E, a fixation implant 2220 comprises onering 2222 (FIG. 93A) or three rings 2222 (FIG. 93B), each ring havingtwo diametrically opposed joints 2224. The implant 2220 may be coupledto a valve annulus, adjacent to a valve annulus, above a valve annulus(superior), below a valve annulus (inferior), or some combinationthereof, for performing annuloplasty, implanting a valve, or for anyother purpose. Each ring 2224 is capable of bending in a lateral planeat each joint 2214, as shown in FIGS. 92C and 92D for a single ring andin FIGS. 92E and 92F for a three ring stack. Fixation elements 2216 areusually provided on at last the terminal ring in each stack.

Referring now to FIGS. 94A and 93B, a fixation implant 2230 comprisesone ring 2232 (FIG. 94A) or three rings 2232 (FIG. 94B), each ringhaving three joints 2234 symmetrically spaced about its circumference.The implant 2230 may be coupled to a valve annulus, adjacent to a valveannulus, above a valve annulus (superior), below a valve annulus(inferior), or some combination thereof, for performing annuloplasty,implanting a valve, or for any other purpose. Each ring 22234 is capableof bending radially inwardly and outwardly. Fixation elements 2236 areusually provided on at last the terminal ring in each stack.

Referring now to FIGS. 95A-95C, a fixation implant 2240 comprises onering 2242 (FIG. 95A) or three rings 2242 (FIG. 95B), each ring havingthree joints 2234 symmetrically spaced about its circumference. Theimplant 2240 may be coupled to a valve annulus, adjacent to a valveannulus, above a valve annulus (superior), below a valve annulus(inferior), or some combination thereof, for performing annuloplasty,implanting a valve, or for any other purpose. Each ring 2234 is capableof bending in lateral plane, as shown in FIG. 95C. Fixation elements2246 are usually provided on at last the terminal ring in each stack.

Referring now FIGS. 96A and 96 B, a skirt 2250 formed for example from apolymeric material having perforations is configured to cover at leastone circumferential region (or segment) of a stent prosthesis on theoutside as shown or on the inside (not shown). For convenience, theskirt 250 is shown to cover the closed cell stent 2130 illustrated inFIGS. 89A-89D and described above. In another example (not illustrated),a second skirt may cover over at least one segment or region of thefirst skirt either on the same surface region of the first skirt (outersurface region, outer surface region) or on the other surface region(inner surface region, outer surface region). In one example, theseparation regions and/or joints after formation of discontinuities orbeing allowed to move, allow blood to flow between one skirt and theannulus tissue (the shown figure), and/or between the two skirts, totrap blood in between, and prevent leakage of the blood afterimplantation.

The bending or opening resistance of the crowns of a serpentine or otherscaffold ring can be adjusted in various ways. For example, the forcerequired to open or separate the struts connected to a common crown canbe controlled by forming an opening or void in the crown and optionallyfilling that opening or void with a reinforcement material. As shown inFIGS. 97A-97G, the crown region 2300 joining a first strut 2302 and asecond strut 2304 can have any one of a variety of voids formed therein.The voids can be formed by any conventional stent fabrication technique,such as laser cutting, chemical etching, or the like. Suitablegeometries include the rectangular void 2306, as shown in FIG. 97A; atriangular void 2308, as shown in FIG. 97B; a crescent shaped void 2310,as shown in FIG. 97C; and a quarter annulus void 2312, as shown in FIG.97D. In other instances, a plurality of voids may be provided, such as aplurality of circular voids 2314 as illustrated in FIG. 97E. In stillother instances, voids having different geometries can be provided in asingle crown, such as a circular void 2316 and a crescent-shaped void2318 as illustrated in FIG. 97F. Additionally, the voids need not alwaysoriented in a luminal-abluminal direction. In some instances, they canbe oriented in a circumferential direction as with void 2320 in FIG.97G.

The voids in the scaffolds of the present invention need not extendfully through a thickness or width of the stents scaffold. In otherinstances, they may be formed as channels in all or a portion of thestents. In particular, a stent scaffold 2330 illustrated in FIG. 98A mayinclude struts 2332, crowns 2334, and axial links 2336, some or all ofwhich have a channel 2338 formed along a length or curvature thereof.These channels may optionally be filled with reinforcement materials asdescribed elsewhere herein.

Still further alternatively, a scaffold structure 2340 as illustrated inFIG. 98B, may include struts 2342, crowns 2344, and axial links 2346connecting adjacent rings, each of which may include one or a pluralityof slots 2348 formed there through. Slots 2348 are shown to penetratefully through a thickness of the strut, crown, and in some casesoptionally axial link. It would be appreciated, however, that the slotscould be changed into channels which do not fully penetrate thethickness of the stent component but which are separated by a pluralityof separation walls 2350. Referring now to FIGS. 99A-99C. Crown regions2350 joining a first strut 2352 and a second strut 2354, are end-out invarious ways. For example, in FIG. 99A each strut 2352 and 2354 mayfirst be tapered by forming a ramp 2356 to reduce the thickness of thestrut before joining in to the crown 2350. The crown 2350 may further beend or reduced in its width as indicated by arrows W. Alternatively, asshown in FIG. 99B, the crown 2350 may be end only in the width W.Alternatively, as shown in FIG. 99C, the crown 2350 is reduced inthickness by the transition of ramps 2358, but there is no furtherreduction in width. In all these embodiments, the crown will have areduced strength so that it is open with a lesser opening force and ifthe crown region had not been thinned, it would be appreciated that atleast a portion of the strength may be returned by coating, layering,laminating, or otherwise adding a reinforcing material over all orportion of the thinned-out region of the crown as described elsewhereherein. The reinforcement material will typically be selected so that itwill degrade over time in a vascular or other luminal or physiologicenvironment so that the compliance of the crown may be increased afterimplantation of the associated stent scaffold.

EXAMPLES

The following Examples are offered by way of illustration, not by way oflimitation:

Example 1

A 9 mm long, 0.063 inch OD annealed L605 cobalt chrome tube having awall thickness of about 0.004 inches was marked with stent pattern“similar to FIG. 16 G-4 with shorter tongues” having a key and lockdesign. The key and lock design had either (1) a closed endedconfiguration to restrict separation to a radially in or outdisplacement direction (FIG. 24A) or (2) an open ended configuration toallow separation by both by a radially in or out displacement directionand/or by an axial displacement direction (FIG. 24 B) after detachmentor forming a discontinuity. After laser cutting the open endedconfiguration with a femtosecond laser (FIG. 25A), the stent was cleanedin a hydrochloric acid solution for 2 minutes to remove islands thathave not fallen between the struts, scale and debris, and rinsed inwater to remove residual acid. A mandrel was placed inside the stent,and any islands remaining were removed. The stent was thenelectro-polished in 10% sulfuric acid in ethylene glycol at 20 amps forabout 40 seconds. After electro-polishing (FIG. 25B), short sleeves tojoin the then free ends of the adjacent segments of the stent strutswere made from 0.3 mm lengths of tubing made from a biodegradable 50:50poly(DL-lactide-co-glycolide) with a 0.007 inch ID and a thickness of0.0018 inch. These sleeves were slipped over each key and lock element,and the stent was then heated at 120° C. in an oven for 10 minutes tomelt the polymer tubing and allowed the melted polymer to flow into andover the elements adjacent to the key and lock element (FIG. 25C). Asillustrated, the key and lock components had stubs, wings, anchors, orthe like to improve attachment after bonding with the polymer. Thispolymer adjacent to the key and lock and adjacent to the surface ofthese components effectively locked the key to the lock together untilthe polymer degrades over a preselected time period, typically in 1 to 3months, to the point where the sleeve no longer can hold the key andlock together or polymer adhesion can be overcome by the pulling forcesunder physiological conditions, resulting in separation of the strutsand uncaging of the stent (or at least regions/segments of the stent),further expansion of the stent or at least segments/regions of thestent, and/or vessel enlargement (or at least segments or regions of thevessel) and/or to allow vasomotion. The stent has sufficient radialstrength after being balloon expanded to a deployed configuration, andhave sufficient hoop strength to support the artery after expansion. Thekey and lock are substantially held together until the polymer degradesor softens to the point that it no longer can hold the key and locktogether or the polymer adhesion is overcome by the pulling forces underphysiological conditions, resulting in their detachment or separation,or form discontinuities. The stent was coated with a drug polymer matrixcontaining Novolimus, an m-tor inhibitor to reduce tissue stenosisand/or restenosis. The 3×9 mm stent as cut has a 0.063″ OD (FIG. 26A).The cut/patterned stent was crimped onto a 3.0 mm balloon catheter,packaged, and sterilized using E-beam. The stent was expanded with a 3mm balloon catheter and tested, under conditions simulatingphysiological conditions, for flat plate compression force withoutdetachment of the key and lock elements FIGS. 26B and 26 C). Aftercompression, the stent was post-dilated back to 3 mm diameter, and soakin dichloromethane to degrade/dissolve the biodegradable 50:50poly(DL-lactide-co-glycolide) (see Table 1). This effectively detached(separated, formed discontinuities of) all the keys from locks on thestent. The stent was re-tested for flat plate compression (see Table 1).The stent in this example after detachment (after formation ofdiscontinuities in the separation regions) has a decreased strength, yetcontinues to have sufficient strength to support a body lumen. However,the radial strain (compliance) of the stent (composite compliance) afterforming discontinuities improved (or increased) compared to uponexpansion (or immediately after expansion), allowing the stented segmentto, uncage, allowing the stented segment to have radial compliancecloser to the lumen prior to stent implantation, and/or allowing thestent to further expand and/or contract, and/or allow for lumenenlargement. The high radial strength upon deployment is desired to pushopen the plaque and maintain the open lumen.

TABLE 1 Flat plate compression of stent with attached and detached keyand lock separation region elements. Flat plate 10% Radial CompressionType strength (N) 9 mm Stent with attached (held together) 0.67separation region elements using biodegradable 50:50Poly(DL-lactide-co-glycolide) 9 mm Stent above with separation region0.22 elements detached forming discontinuities

Example 2

A 14 mm long, 0.063 inch OD annealed L605 cobalt chrome tube having awall thickness of about 0.004 inch was marked with stent pattern havinga “long” key and lock design similar to that shown in FIGS. 16g -1 to16G-3 above. This design allowed the key and lock design to move both upand down (radial relative to a tubular axis) as well as in and out(parallel to a tubular axis) directions (FIG. 27A) while at the sametime, the long key and lock protects the adjacent tissue as the key issliding out of the lock. After cutting/patterning, the stent was cleanedin a 20% 1N hydrochloric acid solution for 2 minutes to remove islandsthat have not fallen between the struts, scale and debris, and rinsed inwater to remove residual acid. A mandrel was placed inside the stent,and any island remaining were removed. The stent was thenelectro-polished in 10% sulfuric acid in ethylene glycol at 20 amp forabout 40 seconds. After electro-polishing, a 150 mg/mL solution ofbiodegradable 50:50 poly(DL-lactide-co-glycolide) in dichloromethanesolvent was applied adjacent to each long key and lock element. After afew seconds to allow for partial evaporation of the solvent, the tip ofa soldering iron is placed adjacent to the element to reflow the polymerbetween the key and lock and on top of the lock. The stent was thenheated at 120° C. oven for 10 minutes to melt the polymer tubing andallowed it to flow into and over the elements adjacent to the key andlock element (FIG. 27B). In addition to the key and lock, the key andlock components have stubs or wings or the like to protect adjacenttissue from being stab by the lock as well as to improve attachmentafter bonding with the polymer. This polymer in between the key and lockand adjacent to the surface of these components effectively locks thekey to the lock together forming the separation region until the polymerdegrades in 1 to 3 months to the point that it no longer can hold thekey and lock together or the degrading polymer adhesion is overcome bythe pulling forces under physiological conditions, resulting in theirdetachment and uncaging of the stent and/or the vessel and/or allowingvasomotion after detachment and/or allowing the stent to further expand.The stent has sufficient strength and can support the artery immediatelyafter expansion. The stent is coated with a drug polymer matrixcontaining Novolimus, an immunosuppressant to reduce tissue stenosisand/or restenosis. The 3×14 mm stent as cut has a 0.063″ OD (FIG. 28).The cut stent was crimped onto a 3.0 mm balloon, packaged, andsterilized using E-beam. The stent was expanded with a 3 mm ballooncatheter and tested for flat plate compression strength (FIGS. 29 and30). After compression, the stent was post-dilated back to 3 mmdiameter, and soaked in dichloromethane to dissolve the biodegradable50:50 poly(DL-lactide-co-glycolide) (see Table 1) to formdiscontinuities simulating physiologic conditions. This effectivelydetached all the keys from locks on the stent. The stent was re-testedfor flat plate compression strength (see Table 2). The stent is testedeither separately, or expanded within a thin tube into the inner wall ofthe thin tube (sufficiently expanded to embed into the inner wall of thethin tube). The use of thin tube is especially important when the stentis configured to separate into two or more longitudinal segments, thetube thus providing a containment means to perform the strength orcompliance tests by testing composite strength or composite (the stentand the tube together) compliance of the stented tube, mimicking thecomposite compliance of the stented segment).

TABLE 2 Flat plate radial compression strength of stent with attachedand detached key and lock elements. Radial strength flat plate (10%Compression) Type (N) 14 mm Stent with attached (held together) 1.07separation regions using biodegradable 50:50Poly(DL-lactide-co-glycolide) 14 mm Stent above with separation regions0.31 detached (discontinuities formed)

Example 3

A 9 mm long, 0.063 inch OD annealed L605 cobalt chrome tube having awall thickness of 0.004 inch was marked with stent pattern having a“long” key and lock design similar to that shown in FIGS. 16g -1 to16G-3 above. This design allowed the key and lock design to move both upand down as well as in and out directions (FIG. 31) while at the sametime, the long key and lock protects the adjacent tissue as the key issliding out of the lock. After laser cutting, the stent was cleaned in a20% 1N hydrochloric acid solution for 2 minutes to remove islands thathave not fallen between the struts, scale and debris, and rinsed inwater to remove residual acid. A mandrel was placed inside the stent,and any island remaining were removed. The stent was thenelectro-polished in 10% sulfuric acid in ethylene glycol at 20 amps forabout 40 seconds. After electro-polishing (FIGS. 32A/B), the entirestent is coated with a polymer poly(lactide-co-caprolactone) atdifferent thickness (FIG. 33A/B) in order to control discontinuitiesformation (or detachment) times (duration after implantation). Thepolymer around the key and lock and adjacent to the surface of thesecomponents effectively locks the key to the lock together (hold themtogether) providing separation regions until the polymer starts todegrade, and/or degrades, and or softens in about 1 months to 6 monthsto the point that it no longer can hold the key and lock together or thepolymer adhesion because it has become brittle and is overcome by thepulling forces under physiological conditions, resulting in theirdetachment and uncaging of the stent and/or the vessel and/or allowingvasomotion after detachment (formation of discontinuities). However, thestent has strength sufficient to support the artery after expansion. Allstents were placed over 3.5×14 mm balloon catheters and crimped usingiris crimper using the following parameters: 45° C. temperature; 50 psicrimp pressure; Medium speed for 45 seconds then 2-minute hot hold. Thestents were crimped to about 0.048″ OD. The stents were packaged, andthen sterilized using E-beam. They were measured for profile, and thenexpanded by inflating the balloon to 8 atm. The stents were tested forradial strength using flat plate compression, and radial strength iristest (Table 3).

TABLE 3 Results of flat plate compression and radial strength Radialstrength (10% Radial Radial Coating Expanded Compression Strength #Profile Thickness OD (Flat Plate))* using IRIS 1 0.0492″ 47 um 3.93 mm1.1N 14.2 psi 3 0.0474″ 35 um 3.89 mm 1.3N 16.8 psi 4 0.0480″ 35 um 3.87mm 1.0N 18.2 psi 5 0.0499″ 23 um 3.95 mm 1.2N 16.5 psi 6 0.0477″ 23 um3.93 mm 1.0N 17.1 psi *All results scaled to 10 full functional rings =3.5 × 14 mm stent.

Example 3.5

In this example, stents according to example 3 were built with theaddition of another polymer coating (PLLA) over thepoly(lactide-co-caprolactone) in various thicknesses to provide longertime duration for separation region to detach after deployment inphysiologic conditions. The duration for detachment ranges from 2 monthsto 1 year.

Example 4

A 0.065″ OD 304 Stainless Steel tube with 0.005″ thickness was laser cutwith a Femtosecond laser into a stent pattern with 14 rings with 8crowns per ring. Each ring had 3 crowns having two notches. (FIGS. 32and 33) These notches were present to promote the fracture or separationby fatigue by systolic and diastolic contractions of the artery at sometime after expansion. After cutting, the stent was cleaned in a 20% 1Nhydrochloric acid solution for 2 minutes to remove islands that have notfallen between the struts, scale and debris, and rinsed in water toremove residual acid. A mandrel was placed inside the stent, and anyislands remaining were removed. The stent was then electro-polished in10% sulfuric acid in ethylene glycol at 30 amps for about 40 seconds.Upon expansion in a 3 mm silicone tubing and subjected to acceleratedfatigue using fatigue tester shown in FIG. 35, there was at least onecrown with notches fracturing or separating after 98 days. This stentimmediately after expansion (FIG. 34) had an iris radial strength of 15psi, and a radial strength using flat plate compression 10% strength of1.19N.

Example 5

A sample stent built in accordance with Example 1 and tested against acommercially available DESyne control non-degradable metallic stent wereeach tested in order to compare their radial strains (compositecompliances) in an in vitro model. The material and equipment used were:(1) aE0215 Bose Electroforce 9110-12 Stent Graft Tester with LaserMicrometer, (2) a clear elastic silicone mock artery, 3.2 mm ID×0.5 mmwall, 10A durometer, and (3) a microscope. Each stent was deployed intothe mock artery at 10 atm pressure, sufficient to seat the stent againstthe artery. There was an approximately 2 cm gap between the stents. Thetest stent was dipped into dichloromethane for approximately 1 minute tosubstantially degrade/dissolve the coating holding the separationregions together and therefore forming discontinuities and uncage thestent (simulating physiological conditions to form discontinuities inthe separation regions). The tube with stents was then loaded into theBose Electroforce Stent Graft Tester as shown in FIG. 35. The BoseElectroforce Stent Graft Tester was set to run the vessel atapproximately 5% inner diameter distension (compliance) to approximatelysimulate physiological conditions. Published literature indicates thatfor coronary arteries the healthy vessel distension (compliance) is inthe range of 3.0%-5.0%. The stents were cycled for approximately1,000,000 cycles at about 2 Hz-5 Hz. During the testing, the IDdistension of the un-stented section of tube and both stents wasmeasured with the laser micrometer. The tube radial strain (simulatingvessel compliance) was measured to be 5% in the un-stented section. TheDESyne stent reduced radial strain (compliance) from approximately 5% toapproximately 1% immediately and maintained the composite compliance at1%. This result is consistent with a prior study of non-degradable metaland/or metal alloy commercially available stents conducted for stentsradial strain which showed these stents to range in radial strain(composite compliance) from 0.2 to 0.3% (In the prior study, Un-stentedtube section radial strain (compliance) was 4.4%, DESyne stent was 0.3%,Synergy stent was 0.2%, and Orisiro stent was 0.3%, radial strain(composite compliance)). The test sample stent initially reduced radialstrain (composite compliance) to 1% (the discontinuities in theseparation regions were not fully formed or detached) but increased toand stabilized at a radial strain of about 2-3% as the discontinuitiesformed. The test sample configured in accordance with the presentinvention showed that the initial composite compliance of the stent (thestented segment including the tube compliance) had an initial complianceand the compliance increased after the separation regions formeddiscontinuities. The test also showed that current control initialcomposite compliance (the stented segment compliance) did not changeover time. The test sample also showed that composite compliance as thediscontinuities formed discontinuities was about 200%-300% larger thanthe composite compliance of the control sample (having no separationregions within the rings).

Example 6

A PLLA based polymeric tube with 0.156 inch ID unit and 150 micron wallthickness is laser patterned into a stent frame comprising structuralelements. The structural elements consist of a plurality of sinusoidalrings, and each ring consisting of struts joined by crowns. Each ring isconnected to an adjacent ring via two links 180° apart. The structuralelements have four surface regions, abluminal surface region, luminalsurface region, and two side surface regions. The stent structuralelements thickness ranged from about 50 microns (to accommodate thepieces of metal reinforcement element) to 150 microns (thickness ofpolymeric material adjacent to the fitted metal pieces) and the width ofthe structural elements is about 150 microns. The stent strut length isapproximately 1 mm in length. The stent pattern comprises furthercreating slots on the crown region of every crown, on every ring. Theslots are created from the abluminal surface region and extend into thetwo struts adjacent to each crown. A mandrel is inserted into the stentfor support, and placed under a microscope and press fitting instrument.A piece of L605 Co/Cr solid wire reinforcement element having a diameterof 80 microns and about 1.5 mm length is press fitted into each of theslots created by the laser pattern contouring to the crown region andextending at least partially into the two adjacent strut regions of eachcrown. At least one of the links connecting adjacent rings is alsofitted with a piece of the metal wires reinforcement elements (eitherwith a separate metal piece or with the same metal piece of the adjacentcrown metal piece). The abluminal side of the wire is partiallyprotruding (about 10 microns) from the abluminal surface region afterpress fitting the wire into each slot. The stent is rotated and thepieces of metal are inserted into every slot until all the slots areoccupied with wires. The wire pieces' ends are deburred orelectropolished so they are rounded and atraumatic to adjacent tissueafter the polymer is degraded. The stent is then coated with a polymerdrug matrix comprising PLLA-PGA polymer coating and rapamycin drug inthe concentration of 3:2 polymer to drug matrix. The amount of drug isabout 5 micrograms per mm length of the stent. The stent is patterned toform a 3.0 mm stent diameter by 14 mm length. The stent is then crimpedonto a 3.0 mm diameter by 15 mm working length balloon delivery systemusing heat (about 45° C.) and pressure. The unit is packaged and sentfor e-beam sterilization. The unit is expanded in water at about 37° C.from the crimped configuration to 3.0 mm diameter (labeled diameter ofthe stent). It is tested for inward recoil after deployment (expansion),and also tested for the radial strength force to obtain 10% compressionbetween two flat plates (flat plate 10% compression test), and comparedagainst a sample that has no metallic pieces in the non-slotted crownregions such that the structural elements dimensions are 120 micronsthick by 150 micron width (no slots formed). The flat plate 10%compression test of the PLLA based polymeric material stent strength isabout 0.17N (or 0.012 N/mm stent length) while the wire reinforced PLLAstent flat plate is about 0.25N (or 0.018 N/mm stent length). The inwardrecoil of the polymeric material stent is about 5% and increased overtime to about 7% after expansion. The recoil of the wire reinforcedstent is about 4% and remains about 4% after expansion. The polymericmaterial frame is configured to degrade between 3 months and 2 yearsleaving behind the atraumatic pieces of metallic wire (reinforcementelements) in the vessel wall, maintaining substantially the pattern ofthe reinforcement elements after deployment. The reinforcement elementsafter the polymeric material frame degrades will have discontinuities inthe strut regions on every ring in this example, uncaging the stentand/or vessel wall (or body lumen). In this example, the stent withreinforcement elements has increased strength by about 1.47 times thestent without reinforcement elements. Typically, the range of thestrength increases from 20% to 300%, more typically the stent withreinforcement elements strength will range from 0.25 N/mm stent lengthto 0.07 N/mm stent length, using a 10% flat plate compression test, andthe dimension for the more typically example range from 80 microns thickto 120 microns thick, while the width dimension ranges from 80 micronswide to 150 microns wide. The inward recoil in this example is improvedeither with lower recoil or by having a low recoil that is substantiallymaintained after deployment (expansion).

Example 7

An example similar to example 6 where at least one of the crowns in atleast some rings does not contain reinforcement elements. In thesecrowns there are no slots formed.

Example 8

An example similar to example 6 where the reinforcement elements areembedded completely (in the crown and strut regions). A polymericcoating comprising the same polymeric material of the frame is coated ontop of the reinforcement elements having a thickness of about 10 micronsto fully cover the reinforcement elements, before the drug coatingmatrix is applied.

Example 9

A magnesium based alloy with 0.063 inch ID and 120 micron wall thicknessmetallic tube is laser patterned into a stent frame comprisingstructural elements. The structural elements consist of a plurality ofsinusoidal rings, and each ring consisting of struts joined by crowns.Each ring is connected to an adjacent ring in via two 180° apart links.The structural elements have four surface regions, abluminal surfaceregion, luminal surface region, and two side surface regions. The stentstructural elements thickness ranged from about 50 microns (toaccommodate the pieces of metal) to 120 microns (thickness of polymericmaterial adjacent to the fitted metal pieces) and the width of thestructural elements is about 150 microns. The stent struts length isapproximately 1 mm. The stent pattern comprises further creating slotson the crown region of every crown, on every ring. The slots are createdfrom the abluminal surface region and extend into the two strutsadjacent to each crown. A mandrel is inserted into the stent forsupport, and placed under a microscope and press fitting instrument. Apiece of L605 Co/Cr solid wire reinforcement element having a diameterof 70 microns and about 1.5 mm length is press fitted into each of theslots created by the laser pattern contouring to the crown region andextending at least partially into the two adjacent strut regions of eachcrown. At least one of the links connecting two rings in this example isalso fitted with a piece of the metal wires (or the piece from theadjacent crown). The abluminal surface region of the reinforcementelement is substantially contained within the abluminal surface regionafter press fitting the reinforcement element (or flush with theabluminal surface region of the stent frame). The stent is rotated andthe pieces of metal reinforcement elements are inserted into every slotuntil all the slots are occupied with reinforcement elements. The wirepieces' ends are deburred or electropolished so they are rounded andatraumatic to adjacent tissue before press fitting them into the stentslots. The stent is then coated with a 5 micron thick PLLA basedpolymeric material coating to further secure the reinforcement elementsin the stent frame slots. The stent is then coated with a polymer drugmatrix comprising PLLA-PGA polymer coating and rapamycin drug in theconcentration of 3:2 polymer to drug matrix. The amount of drug is 5micrograms per mm length of the stent. The stent is patterned to form a3.0 mm stent diameter by 14 mm length. The stent is then crimped onto aballoon delivery system using heat and pressure and crimped onto theballoon delivery system. The unit is packaged and sent for e-beamsterilization. The unit is expanded in air. The sample is tested forinward recoil, and the force to obtain 10% compression between two flatplates (flat plate 10% compression test), and compared against a samplethat has no metallic pieces (reinforcement elements) and no slottedregions such that the structural elements dimensions are 120 micronsthick by 150 micron width. The flat plate 10% compression test of themagnesium based material stent strength is about 0.2N (or 0.014 N/mmlength) while the reinforced magnesium stent flat plate is about 0.25N(or 0.018 N/mm stent length). The inward recoil of the magnesiummaterial stent is about 5% and increased over time to about 7% afterexpansion. The recoil of the reinforced stent is about 4% and remainsmaintained at about 4% after expansion. The stent magnesium alloymaterial frame is configured to degrade in a period ranging from 1 monthto 2 years leaving behind the atraumatic pieces of metallic wire(reinforcement elements) in the vessel wall. The PLLA polymeric materialand drug coating matrix are configured to degrade in a period rangingfrom 3 months to 3 years. In this example, the stent with reinforcementelements has increased strength of about 1.25 times the stent withoutreinforcement elements. Typically, the range of the strength increasesfrom 20% to 300%, more typically the stent with reinforcement elementsstrength will range from 0.025 N/mm stent length to 0.07 N/mm stentlength, using a 10% flat plate compression test, and the dimension forthe more typically example range from 80 microns thick to 120 micronsthick, while the width dimension ranges from 80 microns wide to 150microns wide. The inward recoil in this example is improved either withlower recoil or by having a low recoil that is substantially maintainedafter deployment (expansion).

Example 10

An example similar to examples 6 or 9, where the reinforcing elementsare flattened wire having a substantially rectangle cross sectionmeasuring 76 microns thickness by about 64 microns width.

Example 11

An example similar to example 9, where the reinforcement elements areattached to the outer surface (abluminal surface region) of themagnesium crown and/or strut regions using UV light cure adhesive suchas Dymax 1161-M, Loctite 3525, or the like, low viscosity epoxy such asMasterbond EP41SMed, cyanoacrylate such as J&J Dermabond Advance TopicalSkin Adhesive, Ferndale Laboratories Mastisol Liquid Adhesive, LoctiteSuper Glue Gel, combination thereof, or the like. These adhesivematerial are used for attach temporary crowns to tissue, topicalapplication to hold closed easily approximated skin edges of wounds fromsurgical incisions, temporary sutures, and other applications. Theadhesive is applied on between and or on top of the reinforcementelements and the magnesium structural element. The stent frame does notcontain slots in this example.

Example 12

An example similar example 9, where the reinforcement elements areattached to the outer surface (abluminal) of the magnesium crown and/orstrut regions by laser welding using a pulsed YAG laser, diode-pumpedfiber laser, fiber laser, or other lasers. The stent frame in thisexample does not contain slots.

Example 13

An example where the stent is formed from a tube comprises a cobaltchrome alloy layer that is either sandwich between, on top (abluminal),or on the bottom (luminal) of a magnesium alloy layer. The tubing ispatterned into a stent. At least some regions on at least some rings (orat least some crown regions, and/or strut regions, on at least somerings) have the cobalt chrome alloy layer substantially removed bylaser, chemical means, or mechanical means, to provide the stent touncage in (or over) said rings after expansion under physiologicalconditions, where the cobalt chrome alloy provides for the reinforcementelements, and where the stent uncages after the magnesium alloy layerdegrades. Optionally, the stent prosthesis is coated with a layer ofpolymer to control degradation of the stent prosthesis or to furthercontrol degradation of the stent prosthesis. The stent is optionallycoated with a drug polymer matrix. Alternatively, the layering ofmagnesium alloy layer and the cobalt chrome alloy layer can take placeafter patterning.

Example 14

An example where the stent is formed from a tube comprises a cobaltchrome alloy layer that is on top (abluminal) or inside (luminal) of aPLLA based polymeric material layer. The tube is patterned into a stent.At least some regions on at least some rings (or at least some crownregions, and/or strut regions, on at least some rings) have the cobaltchrome alloy layer substantially removed by laser, chemical means, ormechanical means, to provide the stent to uncage after expansion in abody lumen or in water at 37° C., in (or over) said rings afterexpansion under physiological conditions, where the cobalt chrome alloyprovides for the reinforcement elements, and where the stent uncagesafter the PLLA based polymeric material layer degrades. Optionally, thestent is optionally coated with a drug polymer matrix. Alternatively,the layering of the PLLA based polymer layer and the Cobalt Chrome alloylayer can take place after patterning.

Example 15

An example where the stent is formed from a cobalt chrome alloy layerformed as a sheet layer (having the degradable material layer on top, oron the bottom of the cobalt chrome layer), and where the sheet ispatterned, and then treated to remove the cobalt chrome material layerfrom the at least some crowns and/or strut regions. The sheet is rolledand attached (or fused) forming a patterned stent. The removal of theCoCr layer can take place before rolling and attaching the stent, orafter.

Example 16

An example similar to example 1 or 4, where at least one (preferably atleast two) crowns on at least some rings (preferably on each ring)contains stainless spring steel, superelastic nitinol, or shape memorynitinol material, reinforcement elements. The spring steel, orsuperelastic nitinol, is first bent to the contour of the stent crown(or expansion region) prior to attachment to the stent, and configuredto having a bias to open at various conditions such as in air, ambienttemperature, body temperature, or other. These reinforcement elementshave the propensity to spring outward (or open) to further expand thestent after deployment (expansion). For shape memory nitinol, they arebiased to open when they reach (or substantially reach) a programtemperature (such as about body temperature) and thus further expand thestent after deployment or as the degradable material degrades. Afterexpansion of the stent, the spring, superelastic, or shape memorymaterial, will bias the crown (the crown where the reinforcementelements are attached to or embedded in) to further expand, saidexpansion occurring from a range from after deployment to substantialdegradation of the frame material (containing said reinforcementelements or attached to) time period, where the further expansion rangesfrom 0.05 mm to 0.5 mm in diameter. Alternatively, the reinforcementelements can be shaped in an expansion region (crown) shape where theends of the reinforcement element crown are connected (attached orembedded) to two adjacent struts (preferably where the inner surface ofthe reinforcement elopement crown is facing the inner surface of thecrown joining the two struts), and where the reinforcement element crownis attached along any region of the struts, preferably attached to abouta mid-region of the struts.

Example 17

A non-degradable stent formed from a wire or plurality of wirescomprising Cobalt Chrome alloy where the wire has a diameter of 80microns. The wire is shaped into a stent pattern comprising a pluralityof sinusoidal rings (or turns), the rings comprising crowns and struts.Each ring is connected to an adjacent ring in two locations that are180° apart, each location is at or adjacent to the intersection regionof adjacent crowns. At least one, preferably at least some crown regionsand/or at least some strut regions, on at least some rings are cut (orsevered) using laser separating the cut region (or forming adiscontinuity), each end of the cut structural element is deburred androunded. The two ends of the cut region are held together (or contained)by applying or placing a PLLA based degradable polymeric sleeve over thetwo ends of each of the cut structural element and heated to atemperature close to or above melting point of the polymeric degradablematerial so that the material softens (or melts) holding in place saidstructural element ends together. The two ends of the cut structuralelement are abutting (in other example the two ends are apart forming agap ranging from 1 micron to 200 microns). Optionally, a degradableadhesive such as cyanoacrylate is applied at the cut region joining thetwo cut region ends of the struts and/or crowns on said at least somerings. The stent after expansion (deployment) in a body lumen (or inwater at 37° C.) has sufficient strength to support a body lumen. Thestent uncages over the at least some rings (preferably over the entirestented segment), and/or further expands, and/or responds to atherapeutic vasodilator, and/or enlarges the body lumen in the stentedsegment.

Example 18

A non-degradable stent formed from a wire or plurality of wirescomprising Cobalt Chrome alloy where the wire has a diameter of 100microns. The wire is shaped into a stent pattern comprising a pluralityof sinusoidal rings, the rings comprising crowns and struts. Each ringis connected to an adjacent ring in two locations that are 180° apart,each location is at or adjacent to the intersection region of adjacentcrowns. Two strut regions 180° apart (with the subsequent ring cutstruts being 90° offset), on every ring are cut (or severed) using laserseparating the cut region (or forming a discontinuity), each end of thecut structural element is deburred and rounded the edges. The two endsof the cut region are mechanically treated to create or form a hollowcore in the cut wire regions ranging in length from 1 micron to 50microns. The hollow wire core diameter is about 45 microns. A degradablePLLA based polymer filament bridging element having a diameter ofapproximately 40 microns and a length of about 25 microns is fitted intothe hollow wire core region at the cut region bridging the two cut endsof the structural element. The region is heated to melt of soften thepolymer further securing the junction (or holding together thejunction). Optionally, the junction is held together (or contained) byapplying or placing a PLLA based degradable polymeric sleeve (extendingapproximately 100 microns in length and 15 microns in thickness) overthe two ends of the cut structural element and bridging element (thePLLA based degradable filament) and heated to a temperature above Tg andbelow Tm, or Tm+/−20 C, of the polymeric degradable material so that thematerial softens (or melts) holding in place said structural elementends together. The bridging element is extending into the hollow wirecore about 20 microns in each direction (length) and the bridgingelement gap (between the two cut structural elements ends) is about 5microns. The formed stent is 3.5 mm by 18 mm length.

Alternatively, the two ends of the cut structural element can beabutting (while the bridging element is substantially inside the hollowwire core joining the two cut ends).

Alternatively, the sleeve containing the hollow wire core cut region canalso be the bridging element between the two cut ends of the structuralelement.

Optionally, a degradable adhesive such as cyanoacrylate is applied atthe cut region joining the two cut region ends of the struts and/orcrowns on said at least some rings.

Alternatively, at least some one crown on at least some rings are cut inthe crown region. Alternatively, at least one crown and/or strut, on atleast some rings are cut in the crown and/or strut regions.

Alternatively, the stent prosthesis can be formed from a tubular bodycomprising Cobalt Chrome alloy and patterned into a stent, where thestructural elements to be cut are either patterned and then treated tobe removed (or cut), or where the stent is patterned with the structuralelements cut (or removed).

Alternatively, the stent is formed from a sheet comprising CobaltChrome, patterned and rolled into a stent, or rolled into a tube andpatterned into a stent. The structural elements to be removed (or cutcan take place at any of the steps before rolling into a tube, and/orpatterning, and/or after patterning.

The stent is then coated with a polymer drug matrix comprising PLLA-PGApolymer coating and rapamycin drug in the concentration of 3:2 polymerto drug matrix. The amount of drug is about 5 micrograms per mm lengthof the stent. Alternatively, the drug can be coated on the stentprosthesis without a polymer. Alternatively, the drug can be filled intothe hollow wire core and is configured to be released through holesplaced preferably on strut regions or substantially non deformableregions of the stent. The bridging elements can also contain a drug andreleases the drug over time.

The 3.5 mm by 18 mm length stent is crimped onto a 3.5 mm by 20 mmlength delivery system, packages, and sterilized using e-beamsterilization. The stent is deployed in air (or water at 37 C.°) andtested for strength and recoil. The flat plate radial strength 10%compression test of the stent prosthesis is about 1N (or 0.057 N/mmstent length). The inward recoil of the stent is about 5% and remainedsubstantially the same after deployment. The stent bridging elements areconfigured to degrade in a period ranging from 1 month to 2 yearsleaving behind the patterned stent with two separate (discontinued)struts for each ring. The stent after expansion (deployment) in a bodylumen (or in water at 37 C) has sufficient strength to support a bodylumen. The stent uncages, and/or further expands, and/or responds to atherapeutic vasodilator, and/or enlarges the body lumen, in the stentedsegment (over the entire stented segment).

Example 19

A non-degradable stent formed from a wire or plurality of wirescomprising Cobalt Chrome alloy where the wire has a diameter of 100microns. The wire is shaped into a stent pattern comprising a pluralityof sinusoidal rings, the rings comprising crowns and struts. Each ringis connected to an adjacent ring in two locations that are 180° apart,each location is at or adjacent to the intersection region of adjacentcrowns. Two strut regions 180° apart (with the subsequent ring cutstruts being 90° offset), on every ring are cut (or severed) using laserseparating the cut region, forming a discontinuity (gap), each end ofthe cut structural element is deburred and rounded the edges. The formedstent is 3.5 mm by 18 mm length.

Alternatively, at least some one crown on at least some rings are cut inthe crown region forming a gap. Alternatively, at least one crown and/orstrut, on at least some rings are cut in the crown and/or strut regionsforming a gap. Alternatively, the stent prosthesis can be formed from atubular body comprising Cobalt Chrome alloy and patterned into a stent,where the structural elements to be cut are either patterned and thentreated to be removed (or cut), or where the stent is patterned with thestructural elements cut (or removed) forming discontinuities (or gaps).

Alternatively, the stent is formed from a sheet comprising CobaltChrome, patterned and rolled into a tubular stent, or rolled into a tubeand patterned into a stent. The structural elements to be removed (orcut can take place at any of the steps before rolling into a tube,and/or patterning, and/or after patterning, forming the gaps. The stentis then coated with a polymer drug matrix comprising PLLA-PGA polymercoating and rapamycin drug in the concentration of 3:2 polymer to drugmatrix. The amount of drug is about 5 micrograms per mm length of thestent. Alternatively, the drug can be coated on the stent prosthesiswithout a polymer. Alternatively, the drug can be filled into the hollowwire core and is configured to be released through holes placedpreferably on strut regions or substantially non deformable regions ofthe stent.

The 3.5 mm by 18 mm length stent is crimped onto a 3.5 mm by 20 mmlength delivery system, packages, and sterilized using e-beamsterilization. The stent is deployed in air (or water at 37 C.°) andtested for strength and recoil.

In a preferred alternative, the stent is formed as a tubular stent wherethe cut struts are aligned in a nested parallel configuration to eachother in the crimped configuration. The struts are configured to have anindentation (or groove) and a hook on the other strut. The stent uponexpansion to the deployed configuration is expanded in a substantiallyuniform pattern and the struts support one another to open in asubstantially uniform configuration because of the groove and hook,where the coverage of the structural elements in the gap region in theexpanded stent configuration using a maximum circular diameter rangesfrom 0.7 mm to 1.5 mm.

In another preferred alternative, the stent is formed as a tubular stentwhere the cut struts to are aligned in a nested parallel configurationto each other in the crimped configuration. The stent upon expansion tothe deployed configuration is expanded in a substantially uniformpattern and the struts support one another to open in a substantiallyuniform configuration, where the coverage of the structural elements inthe gap region in the expanded stent configuration using a maximumcircular diameter ranges from 0.7 mm to 1.5 mm.

The flat plate 10% compression test of the stent prosthesis in theexpanded configuration is about 0.6N (or 0.033 N/mm stent length). Theinward recoil of the stent is about 6% and remained substantially thesame after deployment. The stent degradable polymer coating configuredto degrade in a period ranging from 3 months to 2 years.

The stent is formed having discontinuities (gaps). The stent isexpandable from a crimped configuration to an expanded largerconfiguration and have sufficient strength to support a body lumen. Thestent is configured to uncage the body lumen after deployment (or upondeployment), exhibit vaso-dilatation ability (or lumen vasodilation),and/or further expand to a larger stent expanded configuration. Thestent structure remains in the body lumen (or lumen wall) substantiallyin the patterned stent configuration with two separate (discontinued)struts for each ring.

The stent after expansion (deployment) in a body lumen (or in water at37° C.) has sufficient strength to support a body lumen. The stentuncages, and/or further expands, and/or responds to a therapeuticvasodilator, and/or enlarges the body lumen, in the stented segment(over the entire stented segment).

It is appreciated that various combinations of the examples and/oraspects and/or embodiments of the disclosure throughout this applicationcan be combined in whole or in part and remain within the scope of thisdisclosure and application.

Example 20

The Test stent configured in accordance with this invention having threeseparation regions every ring were evaluated in the preclinical animalstudy, the Elixir Medical Novolimus drug eluting coronary stent “PR44”which was available in size of 3.25×14 mm, 3.5×14 mm. The stent was“Resolute”—a FDA approved Zotarolimus drug eluting stent from Medtronic,USA which was available in size of 3.0×15 mm. The test and controlstents were implanted in the coronary arteries of domestic farm pigs ata balloon to artery ratio of 1:1.1 (10% overstretch). Vasomotion testingwith Acetylcholine in the device implanted vessels were performed asdescribed below at the 60 and 90 day time points following deviceimplantation: Acetylcholine was infused at 1.25 ml/min for 3 minutesinto the coronary artery via a catheter in the following sequence: a)control (5% dextrose in saline); b) two incremental acetylcholineinfusions: concentrations of 10⁻⁶ and 10⁻⁵ M; and c) 0.5 mg/ml ofnitroglycerine as a bolus intra-coronary injection. Following thebaseline angiographic imaging, angiography was repeated immediatelyafter each infusion (designated post-dextrose, post-ACH1 and post-ACH2angiographies), except for the injection of nitroglycerin (designatedpost-nitro angiography). For the post-nitro angiography, a period of atleast 3 minutes was allowed to elapse before imaging was performed. Atleast 3 minute time period was allowed to elapse between each angiogramand the following infusion. Once the tests are completed for the firstvessel, the test was repeated in the next vessel. A time period of atleast 5 minutes was allowed to elapse between each artery. Angiographicmeasurements were performed for each artery at the various steps of thevasomotion tests. Measurements were made at the stent segment (in atleast 3 locations: proximal segment, mid-segment, and distal segment, aswell as on at least one un-stented segment (distal to stent (scaffold)).The mid segment can give a more accurate measurement as it has lessnoise or interference from unstented segments affecting the proximal ordistal segments of the stent. For each selected angiogram, mean lumendiameter was measured and the percent change in lumen diameter wascalculated to determine the presence or absence of vasomotion followingthe infusion of the vasoactive substance. Vasomotion testing wasperformed at the 60 and 90 day time points in the test and controldevice implanted vessels and the percent change in the lumen diameterfollowing the infusion of acetylcholine and nitroglycerin is shown inFIG. 35A. Results showed significant change in the lumen diameter in themid-segment of the test PR44 device following acetylcholine (10⁻⁵ M) andbolus nitroglycerin injection in contrast to the no or minimal change(as also observed in published studies) observed with the controlResolute stent. PR44 stent exhibited uncaging of the stent within 60days and within 90 days time period from implantation, allowed vesselremodeling within two months period and within three months period, andallowed vessel response to vaso-constriction and vaso-dilation (afterintroduction of vaso-active agents or substances), followingacetylcholine and/or nitroglycerin infusion. In contrast to the cagedResolute stent, which exhibited minimal or no change, change frombaseline after Acetylcholine treatment for PR44 was +0.21 mm to −0.3 mmwhile the resolute control was +0.06 mm to −0.01 mm Change from baselineafter Nitroglycerin treatment for PR44 was +0.17 mm to −0.2 mm while theresolute control was +0.05 mm to −0.02 mm.

At about 6 months following stent implantation, following the vasomotiontesting, the angiographic mean diameter change at about the mid-lengthof the stented segment of the PR44 implanted vessels (n=3), was 0.17 mm.In the case of control Resolute stent implanted vessel segments (n=3),the angiographic mean diameter change at about the mid length of thestented segment was 0.03 mm. These data demonstrate the stent configuredto have separation regions, within the circumferential rings, inaccordance with the present invention exhibited vasomotion of about 5.67times the vasomotion of this control stent without separation regions.The stent of the present invention also demonstrated uncaging of thestent or the stented vessel segment, and allowed substantially greatervasomotion when compared to a control stent without separation regions.The control stent exhibited little vasomotion.

Example 21

Stents are commonly used to hold open body lumens in mammalian anatomicstructures. Such stents typically are non-degradable stents, havesufficient strength to support, or hold open, a body lumen afterdeployment (expansion of the stent) and substantially maintain suchstrength after expansion, and/or substantially maintain such highstrength after expansion for a long time such as at least 10 years, ormore usually for the life of the stent. However, such stents havecircumferential structural elements (such as rings for example),extending around the stent circumference, therefore caging the lumenwith the circumferential structural elements, and causing largecompliance (or radial strain) mismatch between the stent and the stentedlumen, causing a composite compliance that is small in the stentedsegment (smaller than the lumen and stent), or large stiffness mismatch,between the stent and the lumen, thereby aggravating the lumen which cancause inflammation and re-occlusion of the body lumen over time. Inaddition, such large mismatch significantly diminishes the ability ofthe lumen over the stented segment from exhibiting vaso-motion, and/ordiminishes the lumen ability from further expansion, and/or diminishesthe lumen ability from further expansion and/or contraction, underphysiological conditions.

The stents of the present invention are configured to address one ormore of the issues described above. Although it is important for thestent to have sufficient (or high) strength initially after expansion tosupport a body lumen, such (high) strength can be detrimental to thelumen in the long run in one example due to the continuous irritation tothe body lumen and/or due to large compliance or stiffness mismatch. Itis desired in such example to have a stent configured to have an highinitial strength, and a decreased strength after expansion (afterinitial strength) as described in some of the examples in thisapplication. The stent is configured to have decreased strength afterexpansion of the stent, and/or after the body lumen is open, and/orafter the lumen starts to heal, and/or after the lumen heals, and/orafter at least some cellular or tissue covers at least some of the stentstruts. Even though the stent strength decreases after expansion, thestent still has sufficient strength to hold the lumen open, or hassufficient strength to substantially maintain the lumen open, or hassufficient strength to support a body lumen. One or more reasons forhaving a reduced stent being sufficient are that the stent is capable ofsubstantially maintaining the expanded configuration without the needfor the initial strength magnitude, and/or that the lumen has started toheal, or has healed, exerting less crush force on the stent, and/or thatthe lumen after expansion has remodeled to the expanded configurationand requires less support or less stent strength to maintain it in theopen configuration. Furthermore, the stent in some examples of thepresent invention are configured to have higher radial strain(compliance) after expansion compared to prior art, and/or have higherradial strain (compliance) after expansion that is closer the lumencompliance before stenting, and/or have less radial strain mismatchbetween the stent and body lumen, and/or is less stiff after expansioncompared to initial stiffness in the expanded configuration, and/orbeing able to further expand after an initial inward recoil, and/orexhibit further expansion and/or contraction, and/or exhibit vaso-motionin the stented segment, under physiologic conditions.

The stents in the present invention are configured to uncage, or touncage circumferentially, by configuring the stent to have one or morediscontinuities, or one or more discontinuities, along thecircumferential path of the structural elements (such as the rings),thereby uncaging the circumferential elements (or the stent) andproviding for a compliance (or radial strain), or stiffness that iscloser to the body lumen. The stent in a preferred example continues toprovide (or maintains) lumen support through the patterned stentstructure after expansion and/or after formation of discontinuities. Thestent structure in another preferred example maintains one or moreconnections of substantially all adjacent rings after expansion, ormaintains one or more connections of at least some adjacent rings inanother example. In another preferred example, the initial stentstrength after expansion is reduced after an initial higher strengthupon expansion (or immediately after expansion), and/or is reduced as(or while) the compliance (or radial strain) increases.

A discontinuity in the present example is illustrated as a separationregion in circumferential structural elements. The discontinuity inanother example can also be a discontinuity in (for example) materialproperties, or other mechanical properties that allow increased motionin at least some stent segments after stent expansion.

The configuration of having one or more discontinuities affects thestress on the stent material. A continuous tubular stent holds open alumen by forming a substantially rigid “hoop” of material—adiscontinuity in the ring changes the stress state of the stent fromhoop stress to bending stress (with some tangential stress induced byhoop stresses in the artery) in one example, as the area of thediscontinuity is free to flex or bend, and the remaining semi-circularportion of the stent reacts to this flexing.

As an example, a stent 1820 can have a single discontinuity 1822, asillustrated in FIG. 68, to create the longest moment arm in the stent,and therefore has the possibility of creating a large flexural orbending stress. Multiple discontinuities in a ring offer multipleregions of the lumen to return to substantially their original state ofcompliance or closer to it, while shortening the moment arms, reducingthe flexural and/or bending stresses in the stent segments. Threediscontinuities 1824 are illustrated in FIG. 69 and five discontinuities1826 are illustrated in FIG. 70.

FIGS. 68-70 are sectional views of the stent 1820 and thecircumferential position(s) of the discontinuity(ies) can varythroughout the length of the stent, in patterns including (for example)a straight line of discontinuities along the stent length, a zig-zagpattern of discontinuities along the stent length, a spiral pattern ofdiscontinuities along the stent length, or a random arrangement ofdiscontinuities along the stent length. In a preferred example, thestrips maintain their connections between adjacent rings.

Stents with longitudinal discontinuity(ies) such as stent 1800 withthree discontinuities 1824, allow the stent segments to radially expandand contract, as shown in FIGS. 71-72, which in turn allow an arterialwall AW to expand/contract circumferentially, resulting in a morenatural movement in the anatomical lumen. This increased motion could,for example allow for increased blood flow by allowing increased luminalmotion and/or increased cross sectional area of the lumen.

To evaluate the differences (for example, in radial strain orcompliance, stiffness, maximum displacement, and change in crosssectional area) in configurations of the stents with discontinuities(compared to prior art stent which does not have discontinuities), inhow they react under physiologic conditions such as under pulsatileblood pressure, a Finite Element Model of an artery and stent wasconstructed and analyzed. FEA is a powerful tool to compare variousconfigurations and generate results similar and/or comparatively similarto bench or in-vivo testing. The FEA model was subject to a pressure of80 mmHg to simulate a full cycle of blood pressure variance (diastolicto systolic) but can also be modeled at a different pressure change suchas 176 mmHg (3.4 psi). The artery was modeled with a thickness of 0.25mm, as an elastic member with a Poisson's ratio of 0.45 and an elasticmodulus of 362 psi in order to approximate an arterial compliance of 4%under 80 mmHg pressure. Other physiologic conditions including otherarterial compliances and/or simulated pressure levels may be utilized inother examples. The stent material used for all test samples andanalyses was the same non-degradable stainless steel alloy materialpatterned into a stent and configured as in Table 3 for the relevantparameters:

TABLE 3 Number Number of of Crowns Links Stent Outer Stent Stent per perDesign Diameter Thickness Length* Ring Ring “Prior art stent”, no 4 mm 80 μm  9.6 mm  6   3 circumferential Discontinuities (Control example)Stent having no 4 mm  80 μm  9.6 mm  6   0 circumferentialDiscontinuities and no axial links connecting adjacent rings Stenthaving 3 4 mm 100 μm  9.6 mm  6   3 Discontinuities per ring Stenthaving 4 4 mm 100 μm 11.3 mm  8   4 Discontinuities per ring Stenthaving Spiral 4 mm  80 μm 12.6 mm **7 ***2.5 Ring, each ring having 3Discontinuities Stent having Spiral 4 mm 100 μm 12.6 mm **7 ***2.5 Ring,each ring having 3 Discontinuities *Since the analysis is at a slice inthe approximate center of the artery, Stent Length would not affect theanalysis and is presented for information only. **The “Spiral Rings”model is constructed in a continuous spiral. It has 7 crowns for every360° of spiral. ***Due to the nature of the spiral rings design, theaverage number of links between two rings per turn of the spiral ringdesign is reported.

The stents in Table 3 above are substantially the same except for thethickness (as noted) and for the number of crowns (as noted), andwhether they have discontinuities or not (as noted), and the whetherthey have axial links or not (and how many links, as noted), and thelengths (as noted). The stent circumferential rings were substantiallyperpendicular to the stent longitudinal axis in all test samples exceptthe spiral pattern which has circumferential rings that are at an angle(or offset) to the longitudinal length of the stent.

To characterize the deformation or displacement of each design, a slicethrough the approximate center was taken, and the nodal displacements ofthe internal diameter of the artery wall were examined, as shown inFIGS. 73 and 74. These slices correspond approximately to the locationof links (when present) in the design (it is also the location betweenadjacent rings, or between adjacent crowns on adjacent rings), and werelocated close to the middle of the stent to eliminate any local effectsof the end of the stents, and make the results applicable to stents ofarbitrary length.

The FEA model was run and the following were the results: MaximumDiameter, and Radial Strain, and vaso-motion for the different designsare presented below. The displacement data from the finite elementanalysis (from a section between the rings of the stent) was analyzed todetermine the maximum diameter of the I.D. of the artery (as defined bythe two points on the I.D. farthest apart), and the area of the deformedshape determined by numerical integration using radial coordinatesaround the circumference of the arterial shape. The area is used tocalculate an equivalent circular radius, and from that, equivalentradial strain. The radial strain is then compared to the radial strainin the unstented artery, to determine percent of vasomotion retained, astabulated in Table 4 below.

TABLE 4 Between Ring Percent of vasomotion Between Between retained RingRing Radial (compared to Maximum Strain, % un-stented Diameter at (basedon artery, based 80 mmHg cross sectional on cross Design pressureluminal area) sectional area.) Artery Only,  4.16 mm  4.0% 100.0% 80mmHg Pressure “Prior art stent”, with 4.034 mm 0.44%  11.1% nocircumferential Discontinuities (Control example) Stent having no 4.035mm 0.45%  11.4% circumferential Discontinuities and no axial linksconnecting adjacent rings Stent having 3  4.07 mm  1.4%  34.1%Discontinuities per ring Stent having 4  4.09 mm  1.5%  38.3%Discontinuities per ring Stent having Spiral  4.10 mm  1.9%  47.6% Ring,each ring having 3 Discontinuities Stent having Spiral  4.09 mm  1.8% 46.1% Ring, each ring having 3 Discontinuities

FIG. 75 illustrates the cyclic nature of the arterial displacement witha stent in place. For example, for the prior art stent having “0discontinuities”, and for the stent having “0 discontinuities” and noaxial links stents, their curves are almost superimposed, the low pointof the displacement curves corresponds to the point in close proximityto the crown of a ring near the section (which is between two adjacentrings) under examination, which is held relatively stiffly as a resultof having no circumferential discontinuities. It is worth noting thateven though the second sample has no axial links connecting adjacentrings, the stiffness and radial compliance of the stent/artery systemare similar to the prior art stent/artery system stiffness and radialcompliance. The peaks are at the points farthest from the crowns of thestent (mid ring segment).

The FEA model was also run at another section of the artery, as shown inFIGS. 76 and 77. The section used above was between adjacent rings, buta second section of interest would be in the middle of a ring(“Mid-Ring” section). Note that a straight section through the spiralstent strikes each of the seven crowns at a different position, frombetween adjacent rings to mid-rings, and back to between adjacent rings(for the next turn of the spiral).

Mid-Ring Vs. Between Adjacent Ring Results:

The FEA model results showed that the “prior art” (control) stent havingno discontinuities and sample two having no discontinuities and no axiallinks were substantially the same for all parameters evaluated in thisexample. For the purpose of illustrating the analysis of the Mid-Ringresults, the “prior art” (control) stent versus a stent having fourdiscontinuities were chosen. Looking at the difference in displacementgraphically between the control (0 discontinuities) and4-discontinuities graph shows the difference between sections takenbetween adjacent rings (between adjacent crowns), and mid-ring sectionsboth qualitatively and quantitatively in FIG. 78.

Note that the periodicity of each graph doubles from between ringsections to mid-ring sections, because the artery in those sectionstouches the stent a greater number of times (for example, fromapproaching 6 crowns to crossing 12 struts). In the stent withdiscontinuities, this periodicity is masked by the (larger) periodicradial expansion of the discontinuities. For this reason, the sectionlocation has a greater effect on the displacement (both peak andaverage) compared to the prior art 0 discontinuity stent (control).Table 5 below compares mid-ring data to the data from the between ringsection table for radial strain and for cross sectional area(vasomotion).

TABLE 5 Percent of Percent of vasomotion (cross vasomotion sectionalarea) (cross sectional retained (compared area) retained Between MidRing to un-stented artery) (compared to Ring Radial Radial Between Ringun-stented artery) Design Strain (%) Strain (%) Section Mid-Ring SectionArtery Only, 80 mmHg 4.0% 100.0% 0 Discontinuities (control) 0.44% 0.3%11.1%  7.1% 0 Discontinuities, No Links 0.45% 0.3% 11.4%  7.1% 3Discontinuities  1.4% 1.3% 34.1% 31.9% 4 Discontinuities  1.5% 1.5%38.3% 36.8% Spiral Ring, 3 Sep. Regions (80) 1.9%  47.6% Spiral Ring, 3Sep. Regions 1.8%  46.1% (100)

FIGS. 79 and 80 illustrate the comparison in Luminal Maximum Diameterand Luminal Area for each of the above designs.

Finally, the mid-ring can also produce radial strength data comparisons.That is, the pressure required to compress the artery/stent system by agiven amount is inversely proportional to the diametric change at thestent (which is approximated by the mid-ring displacements). See FIG.81.

The FEA model was also used to analyze a control stent configured tohave differing numbers of discontinuities of equal segments or strips.For example, a single discontinuity can form a “C” shaped discontinuityalong the stent length that can open (or uncage the stent) where the twodiscontinuities can separate to form two strips along the length of thestent, and so on. The maximum diameter and cross-sectional area of eachconfiguration is shown in FIGS. 82 and 83.

It is noteworthy that the motion induced by two discontinuities is alonga diametric line (as illustrated below), which resulted in greaterincrease in diameter compared to the design with three discontinuities.Change in luminal area however grows consistently greater with number ofdiscontinuities and showed luminal area was greater with threediscontinuities compared to two.

Note that the compliance of the stent or stent-artery system referred toin the example is the composite compliance.

Example 21 demonstrated that stents with and without axial links hadcomparable composite compliances and comparable radial strengths, andhad little or no differences in the radial strength or compositecompliance of the expanded rings or scaffold. Therefore, stents (orscaffold) with no axial links had little or no change in compositecompliance and radial strength compared to stents with axial links. Incontrast, scaffolds having separation regions within the circumferentialring structures according to the present invention had increasedcomposite compliance and decreased radial strength of the expanded ringsor scaffold after formation of discontinuities.

Example 22

A porcine animal having a control scaffold (DESyne, Elixir Medical Inc,)and a test scaffolds of (PR100RG) having a 6-crown 3-link pattern havingthree evenly spaced separation regions per ring, with the axial linksconnecting adjacent rings was tested and followed up for about 5 months.The test device was coated with a fast degrading lactide copolymercovering the separation regions including the gaps within the separationregions, and covering the stent surfaces (luminal, abluminal, and twoside surface). The coating had an abluminal thickness of about 10microns. The stent was also coated with a top coated of novolimus and alactide copolymer drug matrix. The test scaffold and a control scaffold(DESyne, Elixir Medical Inc,) were implanted in the coronary arteries ofdomestic pig following which they were serially imaged by angiographyand Optimal Coherence Tomography (OCT) at time points from baseline(after expansion (implantation), 2, 3, and about 5 months. The deviceswere evaluated in vivo at multiple time points by OCT imaging to assessdevice formation of discontinuities within the rings, uncaging, uncagingof the stented segment, as well as changes in device area, and lumenareas (study reference: ELX 080). OCT imaging was performed followingdevice implantations (baseline) and at the follow-up time points above.Still images from the OCT pullback of the test device implanted vesselsegment at baseline and at the follow-up time points are shown in FIGS.100A-100D. Discontinuities were observed in the device as early as the 2month follow up time point and subsequent follow up time points as shownin (FIG. 100 B-D). Examples of the discontinuities in the OCT images areshown within the circled areas of the OCT images. The discontinuitiesshow formation of gaps, or struts out of plane with one another (orstruts having different radii from the center of the image or withrespect to each other). The control stent (not shown in the figure)having no separation regions within the rings, had no formation ofdiscontinuities.

Graphical representations of the test results for the test scaffold(PR100RG) of the present invention, and of the control stent (DESyne)using OCT measurements that were taken at three random points along thelength of each scaffold (at about a proximal, at about a mid, and atabout a distal point of the scaffold length), averaged as a mean foreach follow up time point, are shown for baseline, 2, 3, and 5 monthsfollow up time points, showing stents and luminal mean areas for thetest scaffolds of the present invention, and for the control scaffolds(not having separation regions), after implantation in porcine arteries,are shown in FIGS. 101A and 101B. The test scaffold showed somereduction in mean scaffold area at the 2 months time point, the timeperiod where the vessel is healing from injury. However, the testscaffold mean area increased at the 3 months time point and furtherincreased at the 5 months time point. In this example, the scaffold meanarea at 3 months and 5 months time period were larger than the baselinemean scaffold area. The mean scaffold area at about the 5 months timepoint increased from the mean lumen area at baseline. The controlscaffold mean area showed a similar reduction at the 2 months time pointbut remained substantially the same at the 5 months time point. The meanscaffold area for the test scaffold increased from baseline to the 5months follow up timepoint indicating formation of discontinuities,uncaging of the stent or uncaging of the rings having separationregions. In contrast, the control scaffold mean area remainedsubstantially the same or slightly smaller from baseline to the 5 monthstime point follow up.

The FIG. 101A shows the mean lumen area increasing for the test scaffoldfrom the 3 months time point to the 5 months time point, after aninitial reduction of mean lumen area at the two months follow up due toneointimal cell proliferation and the healing process. In contrast, thecontrol stent has substantially the same mean lumen area from the 3months time point to the 5 months time point, after a similar initialreduction at the 2 months time points due to neointimal cellproliferation and the healing process. The test scaffold mean lumen areademonstrated further expansion (or continued expansion), after theinitial reduction due to the healing phase, over the 5 months follow uptime point, indicating uncaging of the scaffold segment (stented vesselsegment). In contrast, the control stent had some mean lumen arearecovery (increase) at the 3 months time point, after the initialreduction due to the neointimal cell proliferation and the healingprocess. However, the mean lumen area after the recovery from thehealing phase at 3 months remained substantially the same at the 5months follow up time period, indicating continued caging of the vessel(or stented segment of the vessel).

Example 23

The composite compliances of conventional 3.5 mm diameter control stentwithout separation regions and 3.5 mm diameter test stents withseparation regions according to the present were tested according to thespecific protocol set forth above for measuring composite and compared.The conventional stent under examination were 8 crown, no-discontinuitycobalt chromium stents with a strut thickness of approximately 0.08 mm.The stent having separation regions were 6 crown stents with 3discontinuities per ring, arranged in a spiral pattern along the lengthof the stent. The cobalt chromium strut thickness was approximately0.075 mm, with a coating thickness of approximately 0.01 mm. Thereference artery measurement was averaged across both tests, and thecompliance of the stented segments compared to the compliance of thereference artery. The results are in Table 6 below.

TABLE 6 Diameter Measurements Stent-Mock Present Invention Vesselsegment Stent-Mock Vessel mid-stent segment mid-stent Reference (averageof 4 (average of 4 samples) artery samples) (no (after formation of(average of Test Condition discontinuities) discontinuities) 4 samples)0 pressure 3.49 mm 3.71 mm 3.48 mm 176 mmHg 3.50 mm 3.76 mm 3.73 mmChange from 0.01 mm 0.05 mm 0.25 mm 0 pressure to 176 mmHg Percentchange 0.4% 1.2% 7.2% in diameter from 0 pressure to 176 mmHg (compositecompliance) at 176 mmHg

The stent with discontinuities, configured in accordance of the presentinvention, displayed approximately 3 times the diameter change of thecontrol stent without discontinuities, indicating an increase incompliance that makes the stented segment with discontinuities behavecloser to the reference artery than the control stented segment withoutdiscontinuities. The composite compliance of the test stent at 176 mmHgwas about 3 times the compliance of the control stent at 176 mmHg.

Although certain embodiments or examples of the disclosure have beendescribed in detail, variations and modifications will be apparent tothose skilled in the art, including embodiments or examples that may notprovide all the features and benefits described herein. It will beunderstood by those skilled in the art that the present disclosureextends beyond the specifically disclosed embodiments or examples toother alternative or additional examples or embodiments and/or uses andobvious modifications and equivalents thereof. In addition, while anumber of variations have been shown and described in varying detail,other modifications, which are within the scope of the presentdisclosure, will be readily apparent to those of skill in the art basedupon this disclosure. It is also contemplated that various combinationsor sub-combinations of the specific features and aspects of theembodiments and examples may be made and still fall within the scope ofthe present disclosure. Accordingly, it should be understood thatvarious features and aspects of the disclosed embodiments can becombined with or substituted for one another in order to form varyingmodes or examples of the present disclosure. Thus, it is intended thatthe scope of the present disclosure herein disclosed should not belimited by the particular disclosed embodiments or examples describedabove. For all of the embodiments and examples described above, thesteps of any methods for example need not be performed sequentially.

What is claimed is:
 1. An endoluminal prosthesis comprising: a scaffold comprising structural elements comprising a plurality of circumferential rings patterned from a non-degradable material, said scaffold being configured to expand from a crimped configuration to an expanded configuration; wherein at least some of the circumferential rings comprise a plurality of struts joined by crowns; wherein at least some of the circumferential rings have at least one separation region located in a strut comprising a break or a gap in said strut separating said strut,; wherein said at least one separation region comprises a lock and key connection comprising a female portion comprising two spaced apart arms and a male portion adapted to fit between the arms of the female portion; and wherein said at least one separation regions comprises a biodegradable polymer and/or adhesive providing a continuous circumferential path around the scaffold before expansion but said separation region is configured to form at least one discontinuity in said circumferential ring after expansion in a physiologic environment; and at least portions of two of the circumferential rings remain axially joined after all discontinuities are formed.
 2. An endoluminal prosthesis as in claim 1, wherein portions of all circumferential rings remain axially joined after all discontinuities are formed.
 3. An endoluminal prosthesis as in claim 1, wherein the scaffold separates into two, three, or four segments along the length of the scaffold after all discontinuities are formed, each segment comprising a plurality of partial circumferential rings, wherein each partial ring remains axially connected to an adjacent partial ring.
 4. An endoluminal prosthesis as in claim 3, wherein the separation lines have axial or spiral geometries.
 5. An endoluminal prosthesis as in claim 1, wherein the circumferential rings form a helical scaffold.
 6. An endoluminal prosthesis as in claim 1, wherein each of the at least some circumferential rings has from one to five struts having a separation region.
 7. An endoluminal prosthesis as in claim 1, wherein the at least one separation region is immobilized during expansion but configured to separate after expansion in the physiologic environment.
 8. An endoluminal prosthesis as in claim 7, wherein the connections allow separation at said connection in circumferential, radial, and/or axial directions.
 9. An endoluminal prosthesis as in claim 1, wherein said non-degradable material comprises a metal or a metal alloy material.
 10. An endoluminal prosthesis as in claim 9, wherein the non degradable metal or metal alloy comprises stainless steel, cobalt alloy, cobalt chrome, platinum, platinum iridium, platinum chromium, platinum rhodium, or nickel titanium.
 11. An endoluminal prosthesis as in claim 1, wherein the circumferential rings are inclined at an angle relative to a longitudinal axis of the scaffold in the crimped configuration.
 12. An endoluminal prosthesis as in claim 1, wherein the scaffold is patterned from a tube, flat substrate, or a bent wire.
 13. An endoluminal prosthesis as in claim 1, wherein the scaffold further comprises at least one drug comprising an m-TOR inhibitor comprising sirolimus, novolimus, biolimus, everolimus, ridaforolimus, temsirolimus, or zotarolimus.
 14. An endoluminal prosthesis as in claim 1, wherein the scaffold further comprises a polymer coating, wherein the polymer coating comprises polylactide, poly-L-lactic acid, poly-DL-lactide, polylactide-co-glycolide, poly(lactic-co-glycolide), poly(n-butylmethacrylate), ethylene vinyl acetate, poly(ethylene-co-vinyl acetate), polyvinyl pyrrolidone, parylene, PVDF-HFP poly(vinylidene fluoride hexafluoropropylene), polystyrene, poly(L-lactide-co-epsilon-caprolactone), or poly(styrene-b-isobutylene-b-styrene).
 15. An endoluminal prosthesis as in claim 1, where said scaffold has a pattern comprising serpentine, zigzag, helical, open cell design, or closed cell design.
 16. An endoluminal prosthesis as in claim 1, wherein the separation regions comprise a pre-formed break or gap in the circumferential ring and is joined by, covered by, or embedded in the biodegradable polymer and/or adhesive which degrades in the physiologic environment.
 17. An endoluminal prosthesis as in claim 1, wherein the biodegradable polymer and/or adhesive comprises polylactide, poly-L-lactide, poly-DL-lactide, polylactide-co-glycolide, poly(L-lactic-co-glycolide), poly(ethylene-co-vinyl acetate), poly(L-lactide-co-epsilon-caprolactone), poly(DL-lactide-co-glycolide), poly(lactide-co-caprolactone), poly(D-lactide), polyglycolide, polycaprolactone, polyhydroxyalkanoate, polyvinyl alcohol, polyvinyl acetate or cyanoacrylate.
 18. An endoluminal prosthesis as in claim 1, wherein the polymer and/or adhesive provides a coating of at least one of the abluminal and luminal surfaces, wherein the polymer and/or adhesive coating is configured to immobilize the separation region and adjacent structural elements when the prosthesis is being expanded from a crimped configuration to an expanded configuration in a physiologic environment.
 19. An endoluminal prosthesis as in claim 18, wherein coated adjacent structural elements comprise one or more of struts, crowns, and/or circumferential rings.
 20. An endoluminal prosthesis as in claim 18, wherein said coating comprises a thickness of from 5 μm to 50 μm.
 21. An endoluminal prosthesis as in claim 1, wherein upon expansion the separation region allows some movement before separation of the separation region.
 22. An endoluminal prosthesis as in claim 1, wherein the gap before expansion in the separation region ranges from 3 μm to 100 μm.
 23. An endoluminal prosthesis as in claim 1, wherein said lock and key junctions are configured with the length of the male portion and corresponding female portion providing a surface area sufficient to provide adhesion or friction to prevent premature separation upon expansion of said scaffold.
 24. An endoluminal prosthesis as in claim 1, wherein said prosthesis following expansion from a crimped configuration to an expanded configuration in a physiologic environment has sufficient strength to support a body lumen and low recoil from said expanded configuration.
 25. An endoluminal prosthesis as in claim 1, wherein two portions of circumferential rings which remain joined by said axial link each have a separation region in a strut adjacent to said axial link.
 26. An endoluminal prosthesis as in claim 1, wherein said lock and key connection is configured such that the male portion remains contained within the corresponding female portion during expansion of said scaffold.
 27. An endoluminal prosthesis, comprising: a scaffold comprising structural elements and having a plurality of circumferential rings patterned from a non-degradable material, said scaffold being configured to expand from a crimped configuration to an initial expanded configuration; wherein at least some of the circumferential rings comprise struts and crowns and have at least one separation region located in a strut, said at least one separation region is configured to form at least one discontinuity in said strut of said circumferential rings after expansion in a physiologic environment and at least portions of two of the circumferential rings remain axially joined after all discontinuities are formed; wherein the discontinuities are configured to allow the scaffold to further expand after recoil from the initial expanded configuration, and wherein said at least one separation region comprises a lock and key junction with both sides of the male and female portions of the junction being in a plane with the structural element in which they reside, and both the male and female portions have substantially the same thickness as each other and adjacent structural elements.
 28. An endoluminal prosthesis as in claim 27, wherein the at least one separation region comprises an elastic material disposed in, over, and/or adjacent to a gap formed in the ring and wherein the elastic material remains intact after expansion in a physiologic environment.
 29. An endoluminal prosthesis, comprising: a scaffold comprising structural elements comprising struts and crowns, said scaffold having a plurality of circumferential rings patterned from a non-degradable material, said scaffold being configured to expand from a crimped configuration to an initial expanded diameter; said scaffold comprising an abluminal, luminal and two side surfaces; wherein at least some of the circumferential rings have at least one separation region configured to form at least one discontinuity in said circumferential rings after expansion in a physiologic environment and at least portions of two of the circumferential rings remain axially joined after all discontinuities are formed; wherein the discontinuities are configured to allow the scaffold to further expand to an expansion diameter larger than the initial expanded diameter, and wherein the at least one separation region comprises a lock and key connection in at least one of said struts comprising a female portion comprising two spaced apart elements and a male portion configured to fit in between the spaced apart elements of the female portion, and the male portion of the connection is about 3.5 to 5 times longer than the width of the structural elements containing said connection; or the male portion of said connection is approximately 40% to 90% of the length of the structural element containing said connection. 